diff --git a/generator/src/generator/Generator.java b/generator/src/generator/Generator.java
index 8028706..4e9e793 100644
--- a/generator/src/generator/Generator.java
+++ b/generator/src/generator/Generator.java
@@ -10,65 +10,69 @@
 
 public class Generator {
 	public static void main(String[] args) throws Exception {
-		if (args.length != 2) {
-			System.err.println("Usage: java -jar StatemachineGenerator.jar <uml> <out_path>");
-			return;
-		}
-
-		var filename = args[0];
-		var out_path = new File(args[1]).toURI().toString();
-
-		var loader = ClassLoader.getSystemClassLoader();
-		
-		var factory = new EglFileGeneratingTemplateFactory();
-		factory.setTemplateRoot(loader.getResource("generator/").toString());
-		factory.setOutputRoot(out_path);
-		factory.setDefaultFormatter(new JavaFormatter());
-		
-		if (filename.endsWith(".uml") || filename.endsWith(".xmi")) {
-			var uml_module = new EgxModule(factory);
-			uml_module.parse(loader.getResource("generator/XmiProgram.egx"));
-			if (!uml_module.getParseProblems().isEmpty()) {
-				System.err.println("Syntax errors found. Exiting.");
-				for (var prob : uml_module.getParseProblems()) {
-					System.err.println(prob.toString());
-				}
+		try {
+			if (args.length != 2) {
+				System.err.println("Usage: java -jar StatemachineGenerator.jar <uml> <out_path>");
 				return;
 			}
 
-			var uml = new UmlModel();
-			uml.setModelFile(filename);
-			uml.setName("UML");
-			uml.load();
-			uml_module.getContext().getModelRepository().addModel(uml);
-			uml_module.getContext().setUserInput(new UserInput());
+			var filename = args[0];
+			var out_path = new File(args[1]).toURI().toString();
 
-			System.out.println("Generating XMI/UML model " + filename + " to " + out_path);
+			var loader = ClassLoader.getSystemClassLoader();
 
-			uml_module.execute();
-		}
+			var factory = new EglFileGeneratingTemplateFactory();
+			factory.setTemplateRoot(loader.getResource("generator/").toString());
+			factory.setOutputRoot(out_path);
+			factory.setDefaultFormatter(new JavaFormatter());
 
-		if (filename.endsWith(".scxml")) {
-			var scxml_module = new EgxModule(factory);
-			scxml_module.parse(loader.getResource("generator/ScxmlProgram.egx"));
-			if (!scxml_module.getParseProblems().isEmpty()) {
-				System.err.println("Syntax errors found. Exiting.");
-				for (var prob : scxml_module.getParseProblems()) {
-					System.err.println(prob.toString());
+			if (filename.endsWith(".uml") || filename.endsWith(".xmi")) {
+				var uml_module = new EgxModule(factory);
+				uml_module.parse(loader.getResource("generator/XmiProgram.egx"));
+				if (!uml_module.getParseProblems().isEmpty()) {
+					System.err.println("Syntax errors found. Exiting.");
+					for (var prob : uml_module.getParseProblems()) {
+						System.err.println(prob.toString());
+					}
+					return;
 				}
-				return;
+
+				var uml = new UmlModel();
+				uml.setModelFile(filename);
+				uml.setName("UML");
+				uml.load();
+				uml_module.getContext().getModelRepository().addModel(uml);
+				uml_module.getContext().setUserInput(new UserInput());
+
+				System.out.println("Generating XMI/UML model " + filename + " to " + out_path);
+
+				uml_module.execute();
 			}
 
-			var scxml = new PlainXmlModel();
-			scxml.setFile(new File(filename));
-			scxml.setName("SCXML");
-			scxml.load();
-			scxml_module.getContext().getModelRepository().addModel(scxml);
-			scxml_module.getContext().setUserInput(new UserInput());
-		
-			System.out.println("Generating SCXML model " + filename + " to " + out_path);
+			if (filename.endsWith(".scxml")) {
+				var scxml_module = new EgxModule(factory);
+				scxml_module.parse(loader.getResource("generator/ScxmlProgram.egx"));
+				if (!scxml_module.getParseProblems().isEmpty()) {
+					System.err.println("Syntax errors found. Exiting.");
+					for (var prob : scxml_module.getParseProblems()) {
+						System.err.println(prob.toString());
+					}
+					return;
+				}
+
+				var scxml = new PlainXmlModel();
+				scxml.setFile(new File(filename));
+				scxml.setName("SCXML");
+				scxml.load();
+				scxml_module.getContext().getModelRepository().addModel(scxml);
+				scxml_module.getContext().setUserInput(new UserInput());
+
+				System.out.println("Generating SCXML model " + filename + " to " + out_path);
 
-			scxml_module.execute();
+				scxml_module.execute();
+			}
+		} catch (Exception ex) {
+			ex.printStackTrace();
 		}
 	}
 }
diff --git a/generator/src/generator/ScxmlModel.egl b/generator/src/generator/ScxmlModel.egl
index da04a7c..321c9f9 100644
--- a/generator/src/generator/ScxmlModel.egl
+++ b/generator/src/generator/ScxmlModel.egl
@@ -22,6 +22,7 @@ operation t_state getModel() : Tuple {
   var result = new Tuple();
   result.name = self.a_id;
   result.id = self.a_id;
+  result.region = null;
 
   if (self.e_onentry.isDefined() and self.e_onentry.e_script.isDefined()) {
   	result.entry = self.e_onentry.e_script.a_src;
diff --git a/generator/src/generator/Transformations.egl b/generator/src/generator/Transformations.egl
index 808de3d..6b523b9 100644
--- a/generator/src/generator/Transformations.egl
+++ b/generator/src/generator/Transformations.egl
@@ -50,6 +50,10 @@ operation Tuple transformRegionTransitions(statemachine : Tuple, parent_state :
 }
 
 operation Tuple transformState(statemachine : Tuple, region : Tuple, parent_state : Tuple) {
+  if ((self.region == null) and self.transitions.isEmpty()) {
+    (statemachine.name + ": No outgoing transitions for state " + self.name).println();
+  }
+
   statemachine.all_states.put(self.id, self);
 
   if (parent_state.isDefined()) {
diff --git a/generator/src/generator/XmiModel.egl b/generator/src/generator/XmiModel.egl
index 5f400b7..ffc3f86 100644
--- a/generator/src/generator/XmiModel.egl
+++ b/generator/src/generator/XmiModel.egl
@@ -12,6 +12,11 @@ operation Region getModel(sm : Tuple) : Tuple {
   var result = new Tuple();
 
   var initial = self.subvertices.select(s | s.isKindOf(Pseudostate) and ((s.kind = PseudostateKind#initial) or (s.kind = PseudostateKind#shallowHistory))).first;
+  if ((initial == null) or (initial.outgoing.first == null)) {
+  	if (self.state != null) {
+      (sm.name + ": Missing initial state in composite state " + self.state.name).println();
+    }
+  }
   result.initial_id = initial.outgoing.first.target.id;
   result.initial_history = (initial.kind = PseudostateKind#shallowHistory);
 
@@ -23,21 +28,30 @@ operation Region getModel(sm : Tuple) : Tuple {
   return result;
 }
 
+operation Behavior getBody() : String {
+  if (self.isKindOf(OpaqueBehavior) and (self.bodies.first != null) and (self.bodies.first != "")) {
+    return self.bodies.first;
+  } else {
+    return self.name;
+  }
+}
+
 operation State getModel(sm : Tuple) : Tuple {
   var result = new Tuple();
   result.name = self.name;
   result.id = self.id;
+  result.region = null;
 
   if (self.container.state != null) {
   	result.parent_state_id = self.container.state.id;
   }
   
   if (self.entry != null) {
-  	result.entry = self.entry.name;
+  	result.entry = self.entry.getBody();
   }
 
   if (self.exit != null) {
-  	result.exit = self.exit.name;
+  	result.exit = self.exit.getBody();
   }
   
   if (not self.regions.isEmpty()) {
@@ -56,11 +70,11 @@ operation Transition getModel(sm : Tuple, state : Tuple, transitions : List) : T
   var result = new Tuple();
   result.start = state.name;
   result.internal = (self.kind != TransitionKind#external);
-  var trigger = self.trigger.first.event
-  if (trigger.isKindOf(SignalEvent)) {
-	result.trigger = trigger.signal.name;
+  var trigger = self.trigger.first.event;
+  if (trigger.isKindOf(SignalEvent) and (trigger.signal != null)) {
+    result.trigger = trigger.signal.name;
   } else {
-	result.trigger = trigger.name;
+    result.trigger = trigger.name;
   }
   result.actions = new List();
   result.guards = new List();
@@ -69,24 +83,25 @@ operation Transition getModel(sm : Tuple, state : Tuple, transitions : List) : T
   return result;
 }
 
+operation Constraint getGuard() : String {
+  var guard = "else";
+  if ((self.specification != null) and self.specification.isKindOf(OpaqueExpression)) {
+    guard = self.specification.bodies.first;
+  } else {
+    guard = self.name;
+  }
+  return guard;
+}
+
 operation Transition getTarget(sm : Tuple, transition : Tuple, transitions : List) {
   if (self.effect != null) {
-	if (self.effect.isKindOf(OpaqueBehavior)) {
-	  	transition.actions.add(self.effect.bodies.first);
-	} else {
-	  	transition.actions.add(self.effect.name);
-	}
+    transition.actions.add(self.effect.getBody());
   }
   if (self.guard != null) {
-    var guard = "else"
-	if ((self.guard.specification != null) and self.guard.specification.isKindOf(OpaqueExpression)) {
-		guard = self.guard.specification.bodies.first
-	} else {
-		guard = self.guard.name
-	}
-	if (guard != "else") {
-		transition.guards.add(guard);
-	}
+    var guard = self.guard.getGuard();
+    if (guard != "else") {
+      transition.guards.add(guard);
+    }
   }
 
   if (self.target.isKindOf(State)) {
@@ -108,9 +123,14 @@ operation Transition getTarget(sm : Tuple, transition : Tuple, transitions : Lis
 }
 
 operation Transition getSortKey() : String {
-  if ((self.guard = null) or (self.guard.name = "else")) {
+  if (self.guard = null) {
     return "999999-";
   }
-  return "0" + self.guard.name;
+
+  var guard = self.guard.getGuard();
+  if (guard != "else") {
+    return "0" + guard;
+  }
+  return "999999-else";
 }
 %]
\ No newline at end of file