What graphic mode have you selected? If you selected DirectX you mostly will get a lot of errors since this mode isn't supported anymore. Select OpenGL instead.
If that dosn't help check your graphicard drivers. One of the older Nvidia drivers gave me a little bug but its gone allready...at least I don't have problems anymore.
That are the usual suspects...if the problem is still there it might be helpfull to know your system specs and what drivers you are using.