sorry i didn't see the first post earlier - as regards flipbook printer crash - it may be that there are some format of avi files that flipbook printer can't read properly - either because a codec is missing or because the video player used in flipbook printer is choking on them.
the fastest way to check if that's the problem is to try loading the sample movie that installs with the program. if that loads ok then the problem is with the codec of the video file.
the easiest solution to that is to convert the avi file to a more standard format using one of the standard free video converters floating around (
http://www.virtualdub.org/) maybe.
perhaps the first person who figures that out can post a little walkthrough.
as for license key, you can get it same place as license keys for all our main programs:
http://www.donationcoder.com/Keys/index.php