Hi Steve,
I don't know what it is with the video attachements but they seem not to work 99% of the time. I was able to upload a movie, but when I tried larger ones, like 8 meg or so, they would always fail.
I imagine what I'll do is turn those file types "off" so it won't give people the option to load them. I am not sure the server would be happy dealing with them anyhow - with the new features we have on the Gallery, Member Rides, and standard attachments we're serving a lot of pictures and bandwidth anyhow. Movies would increase bandwidth usage by a couple orders of magnitude.
Sorry about the trouble.
Ron