i was just wondering if it's possible to clone the content of one Gem window into another and how to do so.
nope. only one instance can be called.
the problem occured to me when i did a projection onto a monitor that was out of sight for me and i needed just a small control-monitoring-window on the computer to see what's actually going on.
simply use a video spliter, either vga, svideo, composite, whatever, depending on your setup.
something like that http://www.gefen.com/kvm/product.jsp?prod_id=1377 i think you can find cheaper ones using only CRT and not DVI
if you have a video out on your board, you could just clone the whole video and use either your vga out or svideo out to monitor. Then, Gem should be of course running in fullscreen and you may need to use for example a midi controller to interact with your patch.
A full software solution could be the use of gem2pdp and use a pdp window as a monitoring thingy, but you're gonna kill down your framerate.
aym3ric.