I called Live Meeting support back when my company still used that piece of crap because a client just got a grey screen.

My company's internal live meeting expert managed to tell me all of the possible options to investigate that the MS guy took 45 minutes to tell me. The guy didn't even know how to turn off pop-up blocker in IE. He told my client she needed to turn off pop up blocker, she asked how, he moved on to his next suggestion.

After 45 minutes of watching him talk to someone on communicator through the LM session he had with me he finally transitioned to tier 2 and they never did call my client back.

I was forced to go on site at the client's expense because MS couldn't figure out why she couldn't use live meeting.

...all this was using a US-based call center rep.