I have tried connect my canon 5D mark 2 camera,and I find the same problem in GEM, I have put pix_video object,but it just open the default cam from the computer. I used a free software called"CamTwist", it can capture an area from your desktop,and it's possible run into Skype or PD. but first you have to open canon's software EOS Utility,open the realtime display window,and then use CamTwist to capture the window on your desktop. it's tricky,quality not very good,but it's working well.

for higher quality,I would like to know the other way to connect my DSLR camera to PD GEM ,like HDMI output .but my MAC and camera's HDMI are both output port. I really don't know how to connect them. firewire port usually I use for sound card.

many thanks!