I probably should have announced this earlier; my apologies for not doing so.
When the forum was transferred back to my server, it caused the load on my server to spike up. I have been gradually trying to troubleshoot this.
A couple of weeks ago, I believed I saw a topic that was causing some problems, so I moved it to a hidden area of the forum (so it would not be accessed); I also tweaked some of the forum settings to try and produce a lighter load.
It worked very well.
So I have now un-tweaked some of the forum settings, to see if it was the topic, or perhaps the settings.
So, some things have changed (things like the number of topics per page for a board, and posts per page for a topic, for example); and may change again.
Feedback is not discouraged, per se; although during testing I may ignore any complaints. ;-) But if something impacts you, and you have a preference, I will take it into consideration, at least, and do what I can.