Alexinzo, did you find any solutions? We are having a similar issue. When a new user signs up, enters their email, and then submits, screen turns white, holds there, needs to be refreshed, and returns to same page. The registration goes through but for the new user. New users are supposed to get an intro letter/auto email (with default password) after they sign up. But even though the new user is signed up, the auto email does not get sent to them to provide them their default password and the welcome letter. Have also been searching the forum any answers. Did you try directly contacting Buddy Press?