diff -r 54aa6c047c7a src/ai/ai_gui.cpp
--- a/src/ai/ai_gui.cpp	Tue Jul 03 21:28:15 2012 +0200
+++ b/src/ai/ai_gui.cpp	Tue Jul 03 22:19:52 2012 +0200
@@ -959,6 +959,23 @@
 }
 
 /**
+ * Set the widget colour of a button based on the
+ * state of the script. (dead or alive)
+ * @param button the button to update
+ * @param dead true if the script is dead, otherwise false
+ * @return true if the colour was changed and the window need to be marked as dirty
+ */
+bool SetScriptButtonColour(NWidgetCore &button, bool dead)
+{
+	Colours colour = dead ? COLOUR_RED : COLOUR_GREY;
+	if (button.colour != colour) {
+		button.colour = colour;
+		return true;
+	}
+	return false;
+}
+
+/**
  * Window with everything an AI prints via ScriptLog.
  */
 struct AIDebugWindow : public QueryStringBaseWindow {
@@ -1084,11 +1101,10 @@
 				dirty = true;
 			}
 
+			/* Mark dead AIs by red background */
 			bool dead = valid && Company::Get(i)->ai_instance->IsDead();
-			Colours colour = dead ? COLOUR_RED : COLOUR_GREY;
-			if (button->colour != colour) {
-				/* Mark dead AIs by red background */
-				button->colour = colour;
+			if (SetScriptButtonColour(*button, dead)) {
+				/* re-paint if the button was updated */
 				dirty = true;
 			}
 
@@ -1101,6 +1117,15 @@
 			DrawCompanyIcon(i, button->pos_x + button->current_x / 2 - 7 + offset, this->GetWidget<NWidgetBase>(WID_AID_COMPANY_BUTTON_START + i)->pos_y + 2 + offset);
 		}
 
+		/* Set button colour for Game Script */
+		GameInstance *game = Game::GetInstance();
+		bool dead = game != NULL && game->IsDead();
+		NWidgetCore *button = this->GetWidget<NWidgetCore>(WID_AID_SCRIPT_GAME);
+		if (SetScriptButtonColour(*button, dead)) {
+			/* re-paint if the button was updated */
+			this->SetDirty();
+		}
+
 		/* If there are no active companies, don't display anything else. */
 		if (ai_debug_company == INVALID_COMPANY) return;