Strange Problem with Plugin-Window on MAC

Hello, 

 

Ive coded another plugin and wanted to try out the GUI. 
Know I started Nuendo and load the plugin, and now the the plugin window is behind the host window and not in the normal plugin window, where you can setup the presets and the bypass. 
There is a black window like in the screenshot. 

I had these problem last year, too. but i cannot remember... 

Anybody an idea? 

Sorry was my 32bit - 64bit problem. 

Everything is fine now.