I'm experiencing something similiar to this too. When the host of a multi-player game I've joined starts the game, the screen fades about 15% like it's going to transition to the loading screen, but then it just freezes there. From that point I can still see the player lineup and chat box and all the lobby stuff. I cannot click on the chat box, Cancel, Search Again or Create a Group. I can click on Friends and Invites. It seems to be intermittent at the moment.
I've experienced situations where more than 4 people were in a multiplayer lobby and where the player lineup was different from different player's perspectives. For example, I was in a group earlier that I thought looked like this:
1. bigfish99 2. mizunodriver 3. me 4. Pistoler
Then all of the sudden, bigfish99 says something like "13under are you gonna start?" On his screen he showed a different lineup:
1. 13under 2. bigfish99 3. mizunodriver 4. me
Very odd indeed.
*EDIT* Now I just had a game that was able to get started. We were on the 2nd green loading between shots and all of the sudden we get "We're sorry, there has been an error with the game. Please close this window and try again later. Thanks, WGT"
*EDIT #2* Wow, just lost another game (blue screen) loading between the first and second holes. I think I'm gonna leave multiplayer alone today.
*EDIT #3* Seems single player is not safe either. I had just made my click to strike my chip on #8 and before the club contacted the ball it blinked for a second and produced the same error that's in my first edit.