I finally got a few things to work, 
thanks for your help so far. 

My script shows a little red circle which can be 
thrown inside the main window and bounces back 
from the edges. 

Here is the source:
www.bokelberg.de/Download/WorldBouncer.cs 

I'm wondering why i can't get a reference to the 
owner of my morph inside the initialize method ? 

bokel