Only working in FireFox

Hi, i installed it on several websites (v 2.0.2) and while everywhere working in FF, it most often doesn’t work at all in IE and sometimes not in Chrome either.
With no working, i mean: for starters: the bottom bar isn’t visible at all.

One site with X theme: FF only
One site with 7 theme: FF and Chrome only
Another site with 7 theme: FF, Chrome and IE ok.

I cant test if it’s plugin-related cause they’re all live sites.

KR