Oh, and something else which mightn’t be obvious, is that topics with new/unread replies in them will show up in black, whereas topics which you’ve read will show up in gray. It’s a bit subtle, and a bit of a low-contrast thing to do, but it’s there.
I think, if you’ve set the 5 categories each to Tracking or Watching, you get a blue dot on any topics which have new content.
I’m not aware of anything to see the topics in order of creation: a new reply will always bump a topic - the topics are always sorted in order of latest update. Edit: aha, see https://retrocomputingforum.com/latest?order=created
There’s still so little traffic here, that simply going through the “what’s new” stuff is easy enough. We only get a few posts per day, hardly any need to organize it further.
Mind, the way I use it, the only category I use is “What’s New”.