Sorry about the not-staying-logged-in issue. This is because we have two URLs, "kumoricon.com/forums" and "kumoricon.org/forums". When you switch between using one and the other, you lose your session and you don't appear logged in until you create a login session using the new URL.
The forums "live" on .com, and are mirrored over to .org. This isn't a problem except that the server setting for the forum for which URL it will use when you initiate a session only permits one URL.
Anyway, the reason this issue started to reappear is because we mixed up the URLs in that setting. It's fixed now. Use .com and you'll be fine.