diff --git a/src/App/App.tsx b/src/App/App.tsx
index a41676a..a794fcd 100644
--- a/src/App/App.tsx
+++ b/src/App/App.tsx
@@ -206,7 +206,7 @@ export function App() {
 
   const plantStates = [];
   let ps = plant.initial(e => {
-    // ...
+    onRaise(e.name, e.param);
   });
   for (let i=0; i<rt.length; i++) {
     const r = rt[i];
diff --git a/src/Plant/DigitalWatch/DigitalWatch.tsx b/src/Plant/DigitalWatch/DigitalWatch.tsx
index 1a25c85..635f19a 100644
--- a/src/Plant/DigitalWatch/DigitalWatch.tsx
+++ b/src/Plant/DigitalWatch/DigitalWatch.tsx
@@ -1,5 +1,3 @@
-import { useRef } from "react";
-
 import imgNote from "./noteSmall.png";
 import imgWatch from "./watch.png";
 import imgWatchLight from "./watch-light.png";
@@ -29,8 +27,7 @@ type DigitalWatchProps = DigitalWatchState & {
 }
 
 export function DigitalWatch({light, h, m, s, alarm, callbacks}: DigitalWatchProps) {
-  console.log(light, h, m);
-  const twoDigits = (n: number) => ("0"+n.toString()).slice(-2);
+  const twoDigits = (n: number) => n < 0 ? "  " : ("0"+n.toString()).slice(-2);
   const hhmmss = `${twoDigits(h)}:${twoDigits(m)}:${twoDigits(s)}`;
 
   return <>
@@ -46,7 +43,7 @@ export function DigitalWatch({light, h, m, s, alarm, callbacks}: DigitalWatchPro
       : <image width="222" height="236" xlinkHref={imgWatch}/>
       }
 
-      <text x="111" y="126" dominant-baseline="middle" text-anchor="middle" fontFamily="digital-font" fontSize={28}>{hhmmss}</text>
+      <text x="111" y="126" dominant-baseline="middle" text-anchor="middle" fontFamily="digital-font" fontSize={28} style={{whiteSpace:'preserve'}}>{hhmmss}</text>
     
       <rect x="0" y="59" width="16" height="16" fill="#fff" fill-opacity="0" 
         onMouseDown={() => callbacks.onTopLeftPressed()}
@@ -117,11 +114,17 @@ export const DigitalWatchPlant: Plant<DigitalWatchProps> = {
     if (inputEvent.name === "setS") {
       return { ...state, s: inputEvent.param };
     }
-    if (inputEvent.name === "setLight") {
-      return { ...state, light: inputEvent.param };
+    if (inputEvent.name === "lightOn") {
+      return { ...state, light: true };
+    }
+    if (inputEvent.name === "lightOff") {
+      return { ...state, light: false };
     }
     if (inputEvent.name === "setAlarm") {
-      return { ...state, alarm: inputEvent.param };
+      return { ...state, alarm: true };
+    }
+    if (inputEvent.name === "unsetAlarm") {
+      return { ...state, alarm: false };
     }
     return state; // unknown event - ignore it
   },
diff --git a/src/VisualEditor/VisualEditor.tsx b/src/VisualEditor/VisualEditor.tsx
index 529a0b3..aab1440 100644
--- a/src/VisualEditor/VisualEditor.tsx
+++ b/src/VisualEditor/VisualEditor.tsx
@@ -474,6 +474,7 @@ export function VisualEditor({state, setState, ast, setAST, rt, errors, setError
           // @ts-ignore
           selection: [
           ...state.rountangles.map(r => ({uid: r.uid, parts: ["left", "top", "right", "bottom"]})),
+          ...state.diamonds.map(d => ({uid: d.uid, parts: ["left", "top", "right", "bottom"]})),
           ...state.arrows.map(a => ({uid: a.uid, parts: ["start", "end"]})),
           ...state.texts.map(t => ({uid: t.uid, parts: ["text"]})),
         ]
diff --git a/src/statecharts/abstract_syntax.ts b/src/statecharts/abstract_syntax.ts
index 574a91f..2ed2531 100644
--- a/src/statecharts/abstract_syntax.ts
+++ b/src/statecharts/abstract_syntax.ts
@@ -142,7 +142,7 @@ export function getPossibleTargets(t: Transition, ts: Map<string, Transition[]>)
 export function computeArena2(t: Transition, ts: Map<string, Transition[]>): OrState {
   const tgts = getPossibleTargets(t, ts);
   let lca = computeLCA2([t.src as ConcreteState, ...tgts]);
-  while (lca.kind !== "or") {
+  while (lca.kind !== "or" || lca === t.src || lca === t.tgt) {
     lca = lca.parent!;
   }
   return lca as OrState;
diff --git a/src/statecharts/actionlang_interpreter.ts b/src/statecharts/actionlang_interpreter.ts
index 7b8e8ad..5ac4b6e 100644
--- a/src/statecharts/actionlang_interpreter.ts
+++ b/src/statecharts/actionlang_interpreter.ts
@@ -19,6 +19,7 @@ const BINARY_OPERATOR_MAP: Map<string, (a: any, b: any) => any> = new Map([
   [">=", (a, b) => a >= b],
   ["<", (a, b) => a < b],
   [">", (a, b) => a > b],
+  ["%", (a, b) => a % b],
 ]);
 
 export function evalExpr(expr: Expression, environment: Environment): any {
diff --git a/src/statecharts/interpreter.ts b/src/statecharts/interpreter.ts
index b425bcc..ecbb219 100644
--- a/src/statecharts/interpreter.ts
+++ b/src/statecharts/interpreter.ts
@@ -169,6 +169,7 @@ export function enterStates(simtime: number, state: ConcreteState, toEnter: Set<
 
 // exit the given state and all its active descendants
 export function exitCurrent(simtime: number, state: ConcreteState, rt: EnteredScope): ActionScope {
+  console.log('exitCurrent', state);
   let {enteredStates, history, ...actionScope} = rt;
 
   if (enteredStates.has(state.uid)) {
@@ -297,6 +298,8 @@ export function fireTransition(simtime: number, t: Transition, ts: Map<string, T
 
   const srcPath = computePath({ancestor: arena, descendant: t.src as ConcreteState}).reverse() as ConcreteState[];
 
+  console.log('arena:', arena, 'srcPath:', srcPath);
+
   // exit src and other states up to arena
   ({environment, history, ...rest} = exitCurrent(simtime, srcPath[0], {environment, enteredStates: mode, history, ...rest}))
   const toExit = getDescendants(arena);
diff --git a/src/statecharts/label_parser.js b/src/statecharts/label_parser.js
index faf153e..552ba62 100644
--- a/src/statecharts/label_parser.js
+++ b/src/statecharts/label_parser.js
@@ -180,12 +180,14 @@ function peg$parse(input, options) {
   const peg$c13 = "!=";
   const peg$c14 = "<=";
   const peg$c15 = ">=";
-  const peg$c16 = "true";
-  const peg$c17 = "false";
-  const peg$c18 = "\"";
-  const peg$c19 = "^";
-  const peg$c20 = "//";
-  const peg$c21 = "\n";
+  const peg$c16 = "||";
+  const peg$c17 = "&&";
+  const peg$c18 = "true";
+  const peg$c19 = "false";
+  const peg$c20 = "\"";
+  const peg$c21 = "^";
+  const peg$c22 = "//";
+  const peg$c23 = "\n";
 
   const peg$r0 = /^[0-9A-Z_a-z]/;
   const peg$r1 = /^[0-9]/;
@@ -216,17 +218,19 @@ function peg$parse(input, options) {
   const peg$e17 = peg$literalExpectation(">=", false);
   const peg$e18 = peg$classExpectation(["<", ">"], false, false, false);
   const peg$e19 = peg$classExpectation(["+", "-"], false, false, false);
-  const peg$e20 = peg$classExpectation(["%", "*", "/"], false, false, false);
-  const peg$e21 = peg$classExpectation(["!", "-"], false, false, false);
-  const peg$e22 = peg$literalExpectation("true", false);
-  const peg$e23 = peg$literalExpectation("false", false);
-  const peg$e24 = peg$literalExpectation("\"", false);
-  const peg$e25 = peg$classExpectation(["\""], true, false, false);
-  const peg$e26 = peg$literalExpectation("^", false);
-  const peg$e27 = peg$classExpectation([" ", "\t", "\n", "\r"], false, false, false);
-  const peg$e28 = peg$literalExpectation("//", false);
-  const peg$e29 = peg$anyExpectation();
-  const peg$e30 = peg$literalExpectation("\n", false);
+  const peg$e20 = peg$literalExpectation("||", false);
+  const peg$e21 = peg$classExpectation(["%", "*", "/"], false, false, false);
+  const peg$e22 = peg$literalExpectation("&&", false);
+  const peg$e23 = peg$classExpectation(["!", "-"], false, false, false);
+  const peg$e24 = peg$literalExpectation("true", false);
+  const peg$e25 = peg$literalExpectation("false", false);
+  const peg$e26 = peg$literalExpectation("\"", false);
+  const peg$e27 = peg$classExpectation(["\""], true, false, false);
+  const peg$e28 = peg$literalExpectation("^", false);
+  const peg$e29 = peg$classExpectation([" ", "\t", "\n", "\r"], false, false, false);
+  const peg$e30 = peg$literalExpectation("//", false);
+  const peg$e31 = peg$anyExpectation();
+  const peg$e32 = peg$literalExpectation("\n", false);
 
   function peg$f0(trigger, guard, actions) {
     return {
@@ -1089,6 +1093,15 @@ function peg$parse(input, options) {
         s5 = peg$FAILED;
         if (peg$silentFails === 0) { peg$fail(peg$e19); }
       }
+      if (s5 === peg$FAILED) {
+        if (input.substr(peg$currPos, 2) === peg$c16) {
+          s5 = peg$c16;
+          peg$currPos += 2;
+        } else {
+          s5 = peg$FAILED;
+          if (peg$silentFails === 0) { peg$fail(peg$e20); }
+        }
+      }
       if (s5 !== peg$FAILED) {
         s6 = peg$parse_();
         s4 = [s4, s5, s6];
@@ -1137,7 +1150,16 @@ function peg$parse(input, options) {
         peg$currPos++;
       } else {
         s5 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e20); }
+        if (peg$silentFails === 0) { peg$fail(peg$e21); }
+      }
+      if (s5 === peg$FAILED) {
+        if (input.substr(peg$currPos, 2) === peg$c17) {
+          s5 = peg$c17;
+          peg$currPos += 2;
+        } else {
+          s5 = peg$FAILED;
+          if (peg$silentFails === 0) { peg$fail(peg$e22); }
+        }
       }
       if (s5 !== peg$FAILED) {
         s6 = peg$parse_();
@@ -1182,7 +1204,7 @@ function peg$parse(input, options) {
       peg$currPos++;
     } else {
       s1 = peg$FAILED;
-      if (peg$silentFails === 0) { peg$fail(peg$e21); }
+      if (peg$silentFails === 0) { peg$fail(peg$e23); }
     }
     if (s1 === peg$FAILED) {
       s1 = null;
@@ -1318,20 +1340,20 @@ function peg$parse(input, options) {
     let s0, s1;
 
     s0 = peg$currPos;
-    if (input.substr(peg$currPos, 4) === peg$c16) {
-      s1 = peg$c16;
+    if (input.substr(peg$currPos, 4) === peg$c18) {
+      s1 = peg$c18;
       peg$currPos += 4;
     } else {
       s1 = peg$FAILED;
-      if (peg$silentFails === 0) { peg$fail(peg$e22); }
+      if (peg$silentFails === 0) { peg$fail(peg$e24); }
     }
     if (s1 === peg$FAILED) {
-      if (input.substr(peg$currPos, 5) === peg$c17) {
-        s1 = peg$c17;
+      if (input.substr(peg$currPos, 5) === peg$c19) {
+        s1 = peg$c19;
         peg$currPos += 5;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e23); }
+        if (peg$silentFails === 0) { peg$fail(peg$e25); }
       }
     }
     if (s1 !== peg$FAILED) {
@@ -1348,11 +1370,11 @@ function peg$parse(input, options) {
 
     s0 = peg$currPos;
     if (input.charCodeAt(peg$currPos) === 34) {
-      s1 = peg$c18;
+      s1 = peg$c20;
       peg$currPos++;
     } else {
       s1 = peg$FAILED;
-      if (peg$silentFails === 0) { peg$fail(peg$e24); }
+      if (peg$silentFails === 0) { peg$fail(peg$e26); }
     }
     if (s1 !== peg$FAILED) {
       s2 = [];
@@ -1361,7 +1383,7 @@ function peg$parse(input, options) {
         peg$currPos++;
       } else {
         s3 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e25); }
+        if (peg$silentFails === 0) { peg$fail(peg$e27); }
       }
       while (s3 !== peg$FAILED) {
         s2.push(s3);
@@ -1370,15 +1392,15 @@ function peg$parse(input, options) {
           peg$currPos++;
         } else {
           s3 = peg$FAILED;
-          if (peg$silentFails === 0) { peg$fail(peg$e25); }
+          if (peg$silentFails === 0) { peg$fail(peg$e27); }
         }
       }
       if (input.charCodeAt(peg$currPos) === 34) {
-        s3 = peg$c18;
+        s3 = peg$c20;
         peg$currPos++;
       } else {
         s3 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e24); }
+        if (peg$silentFails === 0) { peg$fail(peg$e26); }
       }
       if (s3 !== peg$FAILED) {
         peg$savedPos = s0;
@@ -1400,11 +1422,11 @@ function peg$parse(input, options) {
 
     s0 = peg$currPos;
     if (input.charCodeAt(peg$currPos) === 94) {
-      s1 = peg$c19;
+      s1 = peg$c21;
       peg$currPos++;
     } else {
       s1 = peg$FAILED;
-      if (peg$silentFails === 0) { peg$fail(peg$e26); }
+      if (peg$silentFails === 0) { peg$fail(peg$e28); }
     }
     if (s1 !== peg$FAILED) {
       s2 = peg$parse_();
@@ -1473,7 +1495,7 @@ function peg$parse(input, options) {
         peg$currPos++;
       } else {
         s2 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e27); }
+        if (peg$silentFails === 0) { peg$fail(peg$e29); }
       }
     }
     while (s2 !== peg$FAILED) {
@@ -1485,7 +1507,7 @@ function peg$parse(input, options) {
           peg$currPos++;
         } else {
           s2 = peg$FAILED;
-          if (peg$silentFails === 0) { peg$fail(peg$e27); }
+          if (peg$silentFails === 0) { peg$fail(peg$e29); }
         }
       }
     }
@@ -1501,12 +1523,12 @@ function peg$parse(input, options) {
     let s0, s1, s2, s3, s4, s5, s6;
 
     s0 = peg$currPos;
-    if (input.substr(peg$currPos, 2) === peg$c20) {
-      s1 = peg$c20;
+    if (input.substr(peg$currPos, 2) === peg$c22) {
+      s1 = peg$c22;
       peg$currPos += 2;
     } else {
       s1 = peg$FAILED;
-      if (peg$silentFails === 0) { peg$fail(peg$e28); }
+      if (peg$silentFails === 0) { peg$fail(peg$e30); }
     }
     if (s1 !== peg$FAILED) {
       s2 = peg$parse_();
@@ -1516,7 +1538,7 @@ function peg$parse(input, options) {
         peg$currPos++;
       } else {
         s4 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e29); }
+        if (peg$silentFails === 0) { peg$fail(peg$e31); }
       }
       while (s4 !== peg$FAILED) {
         s3.push(s4);
@@ -1525,16 +1547,16 @@ function peg$parse(input, options) {
           peg$currPos++;
         } else {
           s4 = peg$FAILED;
-          if (peg$silentFails === 0) { peg$fail(peg$e29); }
+          if (peg$silentFails === 0) { peg$fail(peg$e31); }
         }
       }
       s4 = peg$parse_();
       if (input.charCodeAt(peg$currPos) === 10) {
-        s5 = peg$c21;
+        s5 = peg$c23;
         peg$currPos++;
       } else {
         s5 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$e30); }
+        if (peg$silentFails === 0) { peg$fail(peg$e32); }
       }
       if (s5 === peg$FAILED) {
         s5 = peg$currPos;
@@ -1544,7 +1566,7 @@ function peg$parse(input, options) {
           peg$currPos++;
         } else {
           s6 = peg$FAILED;
-          if (peg$silentFails === 0) { peg$fail(peg$e29); }
+          if (peg$silentFails === 0) { peg$fail(peg$e31); }
         }
         peg$silentFails--;
         if (s6 === peg$FAILED) {
diff --git a/src/statecharts/transition_label.grammar b/src/statecharts/transition_label.grammar
index 91a097c..865973a 100644
--- a/src/statecharts/transition_label.grammar
+++ b/src/statecharts/transition_label.grammar
@@ -69,7 +69,7 @@ compare = sum:sum rest:((_ ("==" / "!=" / "<=" / ">=" / "<" / ">") _) compare)?
     };
 }
 
-sum = prod:product rest:((_ ("+" / "-") _) sum)? {
+sum = prod:product rest:((_ ("+" / "-" / "||") _) sum)? {
 	if (rest === null) {
     	return prod;
     }
@@ -81,7 +81,7 @@ sum = prod:product rest:((_ ("+" / "-") _) sum)? {
     };
 }
 
-product = atom:unary rest:((_ ("*" / "/" / "%" ) _) product)? {
+product = atom:unary rest:((_ ("*" / "/" / "%" / "&&" ) _) product)? {
 	if (rest === null) {
     	return atom;
     }
diff --git a/todo.txt b/todo.txt
index 6578174..7f519cb 100644
--- a/todo.txt
+++ b/todo.txt
@@ -35,6 +35,8 @@ TODO
 
 - usability stuff:
     - show internal events
+    - hovering over event in side panel should highlight all occurrences of the event in the SC
+    - hovering over error in bottom panel should highlight that rror in the SC
     - highlight selected shapes while making a selection
     - comments sometimes snap to transitions even if they belong to a state
     - highlight fired transitions