One of the problems we've had here is there are random bursts of errors from different mods, that's something I'm trying to correct with clean install. Don't know what's causing this, afaik RCR hasn't been making any changes to the forum. I'm working on the rebuild in a clone install in separate directory connected to same database, when I want to try it live I flip the dir names, then flip them back when I'm done. It's possible bots are hitting the clone and somehow triggering errors, but most of the errors are coming from mods that are installed in production forum, not in clone. Been wasting a lot of time working with a new responsive theme, think I'll go to Plan D and just do a clean install with your current theme and add responsive theme after forum is cleaned up.
There are also problems with the server, I have a clone install running on my server, same database, it runs much faster there, but is as slow here as your current install. Two nights ago I got an exceeded resources error that took the forum down for a short time, that should never happen with just the forum and blog running in the account. RCR has a support ticket in with host, but this has been an ongoing problem for quite a while, will be surprised if they can fix it.