QUESTION: - I find that movies in.avi format will not play on my iMac, though I uploaded easily to Vimeo. I also found that apparently they cannot be converted to any other format. Does this mean that files created via Bogart for export to the internet can only be played there? And does this then mean that I must generate the film in a different way if I want to view it on my computer?

ANSWER:  Many folks experience this -- a file that will export from your Casablanca editor (could also be another video editor running on a Mac or WIndows PC) but will not play back on that computer (outside of the editor).

This is not necessarily a problem, just means that on your computer you don't have a compatible player that will successfully open and/or play back that specific file format.

I would recommend downloading and using the VLC Player - this is an open-source (free ware) program that will play back most any video file you can throw at it.  You can download this software and read more details about it here: http://www.videolan.org/vlc/index.html