Well, it seems that part of the problems I saw earlier when trying to upgrade Remository were caused by some strange interaction with the Xaneon extensions (which updated smoothly, or so it seemed).
Having nice URLs such as ‘/articles/rant/broken_stuff’ is good, but I’d rather have a working up-to-date repository component, so the decision was easy: Out with the Xaneon extension, and in with the new Remository (which is now being developed by Black Sheep Research).
Could this be the cause of the problems I had with the zOOm gallery? I’ll got to check that out.