If you mean Theora , I do not like the quality of them and AVI is far too big, the frames stream off the harddrive and are in jpeg format so no worries on size etc, it works very well on 800 x 600 sprites and sounds attached to certain frames.
When I run the game the sprites seem fine, and they preview no problem in project manager its in sprite edit that the issue occurrs.
Cannot send the sprite as it is far to big to send via email, but if you create a 8700 x 600 screen that is black and one that is red and create a sprite with say 100 frames or more you should be able to see what I mean.
Also content of project is under contract to a publisher so I cannot send any data belonging to the project.