Hi,
I can’t play a multiplayer game, I clicked the online button and it asked me for my key which it said was valid, then I entered my username which was also valid. Then it just sat there unchanging. The game didn’t exactly lock up since I can just hit escape to go back to the main menu. If I close the game and restart it, I just end up at that stuck screen again.
I’m using a Macbook Pro with a 2.4 GHz Core 2 Duo and 8GB RAM.
I have provided a screenshot below.
To me that screen seems correct.
You are now registered online and ready to go.
Quick question: when you go back to the main menu, can you access the Online and Challenges buttons ?
Yeah… sorry I thought online meant I could go there to play against people that are currently online. After you asked that question I went back to Read The F****** Manual online and yeah… Don’t mind me. The Online screen’s function isn’t obvious when compared to the flow of most other games. A tutorial tooltip that explains that entering your registration data is all you need there would be good. Or an “OK” button that takes you back to the Main Menu or one that says “Play Challenges” and takes you there would probably be a better interface design. Orrrr… everyone could read the manual, but I though that’s what tutorials are for hehe.
Sorry for wasting electrons, photons and time here.
No stress, chief 
Glad to see that it is all working