I just tried it since my mac is much faster usually than my older PC but it wouldn't see any of my video files.
Though the file name says "ppc" in it, it run on my intel mac.

Hello,

I was experimenting with the chroma key effects. I was able to use a background video and put my chroma key video on top of it. Unfortunately my background video was 3 seconds shorter than my foreground video. But since I don't have audio in the background video I wasn't able to set loop points in it. Is it a bug/oversight? Or am I missing something to make the background video loop properly? Thanks for your help!