Though I believe EE tries to be as compatible as possible with as many browsers as possible, the developers cannot always fix problems that happen in non-mainstream (aka possibly non-compliant and independently written) browsers.

The fact is; problems can arise in situations like this and it it becomes difficult/impossible to diagnose exactly where the problem is coming from and whether or not the problem is even 'fixable' on the game-side end of things.

I'm glad you switched to a browser where things work for you. At least Opera is known to be stable and pretty compliant. I hope you don't have any more problems!

At least now, if you have any issues, it should be a little more traceable and 'friendly' to work with.