Same directory, I'd never had this sort of problem with updating the version before. I manually edited the demon names back into the preferences file while Kolmafia was closed, relaunched r9453... and the names were blanked out again. Closed it once more, re-edited the pref file, and opened the prior version (r9429) and the Demon Names were still there. It's hard to tell if any other preferences were lost, though it did also forget that I'd done Breakfast today.