thats coz ur using shitty ati drivers

10.7?
easiest fix would be to extract
>>this<< to your ET folder (where the ET.exe is/works for other opengl games as well)
ati played around with opengl, updated it a bit but *i-need-a-broader-vocab* it up for old games... not sure in which version its fixed (maybe 10.8 ) but thats a good workaround if u wanna keep the current drivers u have.
getting kicked by pb...fail. just browse through the "general support pc" section and u'll find everything u need to know, if not open a new thread.