Think I was having a similar problem, since the new software. Constantly having to log-in, even though I thought I was!
Checked 'user cp', 'edit options' and I had originally replied 'yes' to 'browse board with cookies?', which I thought should keep me logged in for a session.
I've just changed the reply to 'no', and now I stay logged in !!
Don't quite understand why, but it seems to have solved my problem !!
