Strange error in GUI

Hi,

I am trying the demo version of TGB right now.
First of all it would be very convinient to be able to select earlier created menus in the GUI editor just from the file menu and open them for editing.

Experimenting with the GUI editor presents me with a strange effect.
I create a new GUI (File->New GUI)
I drop a GUIButtonCtrl in the middle of the screen and give it some text.

Now I save the gui and click on Toggle GUI editor.
Now TGB seams to be hanging. My mouse pointer is painted all over the TGB window if I move it and the only thing I am able to do is closing TGB.

Now I load the same GUI in Torque script. I exec it in the initializeProject in main.CS and load it in startGame with Canvas.setContent(startGui)

Next I start the game and the GUI shows. However, when I move my mouse, again it paints the screen full with the mouse pointer.

Are there some basic requirements that must be met when using the GUI I am missing?
Or is this a bug?

Being able to create a GUI with an editor is one of the selling points of TGB to me.

Thanks.