Problem creating profile

[[ITA] YouF]

I changed username to play game and when I try to join Internet games I'm blocked in a screen where is visible only the background of the game without any menu.
If I click for exit appear a window where I can login or create a profile, but after I inserted username, password and e-mail and after I checked the game policy, it's all blocked, doesn't happen anything, and I don't receive any e-mail, am I doing something wrong? And why this happens only since I changed the name of Steam profile?