Well the thing about using things like flash on a proxy is it compromises your anonymity.
However...compromises doesn't mean give-away in a heart beat. A lot of the proxies that allow for flash have limited usage (and aren't as secure). Try this video and the tor browser: (you need an account to see links)
I haven't watched it completely but it looks like it'll work. When doing these things like allowing scripts tor will warn you that your anonymity is being compromised.
@(you need an account to see links) Ack I should have clarified. The only issue is that Flash sometimes compromises your IP, so I'm looking for something that'll keep it safe while using Flash.