I didn't know what you were talking about to start with because I've never set up ranks. Is this something that was added in an update as a default setting?
I didn't think to look at ranks as I've never used them. How would they suddenly appear when I've never added them? I find it really odd that this only seemed to happen after the update too. But yeah, it does seem a problem if a new user can end up unassigned like this.
For the login issue, I've never seen that happen but could it be a cache issue? As an admin it doesn't cache anything for me. I'm using W3 Total Cache for use with a CDN. I've got “/forum/” in the “Never cache the following pages:” option. But maybe that's not working or is set up incorrectly?
Finally, I really want to keep up helping as and when I can, I just don't seem to be as much use as I thought I might be. I spent a few days staring blankly at the source code, just understanding how everything works together with WordPress was a headache. I don't want to hold you back with stupid questions.
I'll help out with the wiki for version 5 and I'll check out what you have for the new version and look at the code again now it's been a few weeks. It just seems like I'm facing a huge wall in trying to get to grips with how everything works.