http://bugs.winehq.org/show_bug.cgi?id=22417
--- Comment #5 from Matthew Bauer mjbauer95@gmail.com 2010-04-26 16:49:20 --- I've finally got a PlayOnLinux script for Roblox that works:
http://github.com/paradoq/playonlinux/raw/master/roblox.pol
I think the problem is that I did not have the option to allow DirectX to stop the mouse leaving the window enabled. I think once that is enabled everything is working.