Ah - I just found an unresolved bug. I'm assuming it's been reported before, but just in case...
When you upgrade the Dark Sanctum, it stops recruiting new cubi. This is presumably because up_recruitment replaces, rather than adds to, the previous recruitment number - and up_recruitment is set to 0 for the sanctum upgrade. It should easily be fixed by changing up_recruitment to 1.
I’d noticed the dark sanctum had stopped recruiting when I upgraded, as well. I had thought it might have been due to a different bug I’d found, but I don’t know much about ren’py, so your explanation makes way more sense.
That other bug, though, is that you seem to be able to upgrade the tavern and dark sanctum to level 2 without meeting any of the requirements beyond having the level 1 variants constructed.
While we’re reporting bugs, sorry to go back to this one, but you guys remember that bug where villages weren’t getting added to your total count in certain events? Not sure if this is on purpose, but I can confirm that the village events “orc wants to lead,” “old hero occupy,” “old hero trade,” and “old hero destroy” have no effect on your village count or income from villages. Also the one where you just pass through and have dinner with some girl and her family, though that one seemed intentional. So far the only events in my latest playthrough (0.2.62b, still early pre-week 20) I’ve noticed increase village count and village income are the generic capture/trade events, the corrupt noble event, and the event with the coven trying to sacrifice a guy the name of which I can’t conveniently recall at the moment, which were the only events that worked back in my first significant plauthrough in v0.2.43.