I haven't had any problems moving with a mouse and keyboard. Well actually I use a trackball (have for ump-teen years) but it's basically the same. Try acrobatics- have found it the easiest and most controllable for a mouse+keyboard. The chat system sucks like a Hoover.

It's not a perfect game by any means- but it is fun! We can nitpick any game and some with justification. Outside of the chat system and maybe a need for a tad more content at a few levels. There's not really any outstanding flaws I can see.