diff --git a/src/gui/__init__.py b/src/gui/__init__.py
--- a/src/gui/__init__.py
+++ b/src/gui/__init__.py
@@ -21,14 +21,15 @@ class GUI:
 		self.root.option_add('*tearOff',False) # for menu
 
 		self.detector=ImageAnalyzer()
+		self._frame=None
 		self._frameKey=0
 
 		self._ownMessages=None
 		self._coreMessages=None
 
-		self._state=GUI.SETUP
+		self._state=GUI.RECORDING
 
-		self.mainWindow = MainWindow(self, master=self.root)
+		self.mainWindow = MainWindow(self)
 		self.settings=None
 		self.root.columnconfigure(0,weight=1)
 		self.root.rowconfigure(0,weight=1)
@@ -39,7 +40,7 @@ class GUI:
 		self.root.bind("<F12>",lambda e: Settings(self))
 		self.mainWindow.bind("<Destroy>",lambda e: self._shutDown())
 
-		self.setUp()
+		self.setRecording()
 
 	def __call__(self,ownMessages,coreMessages):
 		self._ownMessages=ownMessages
@@ -57,6 +58,7 @@ class GUI:
 		self.mainWindow.setUp()
 		self.root.bind("<Left>",lambda e: self.sendMsg("prevFrame"))
 		self.root.bind("<Right>",lambda e: self.sendMsg("nextFrame"))
+		self._state=GUI.SETUP
 
 	def setRecording(self):
 		self.mainWindow.setRecording()
@@ -65,11 +67,16 @@ class GUI:
 		if self.settings:
 			self.settings.destroy()
 			self.settings=None
-		self.sendParams()
+		if self._coreMessages: self.sendParams()
+		self._state=GUI.RECORDING
 
 	def sendParams(self):
 		self.sendMsg("setParams",(self.detector.params.copy(),))
 
+	def preview(self):
+		if self.detector.analyze(self._frame):
+			self.mainWindow.boardView.redrawState(self.detector.board)
+
 	def _shutDown(self):
 		log.info("GUI proc exiting.")
 		self._ownMessages.send("!kill",("gui",))
@@ -89,11 +96,15 @@ class GUI:
 		if self._state!=type and self.mainWindow.imgView.isSet():
 			log.info("ignored setFrame event, wrong type")
 			return
+		self._frame=frame
 		self._frameKey=key
 		self.mainWindow.setFrame(frame)
 		self.root.event_generate("<<redrawImgView>>")
 
 	def _stateHandler(self,gameState,moves):
+		if self._state==GUI.SETUP:
+			log.info("ignored incoming gameState")
+			return
 		labels={(row,col):(i+1) for (i,(c,row,col)) in enumerate(moves)}
 		self.mainWindow.boardView.redrawState(gameState,labels)