Mimi wrote:
I do seem to have lost some progress. I definitely completed the game on ‘Harder Still’ yesterday, and opened up the next difficulty, but it’s reverted to Harder Still being the next difficulty again. It’s not a problem, and may have been because of the rogue 9th book which popped up after I had completed the game, but thought you’d want to know.
If it popped the unlock on the screen when you'd completed the game (the little one, not the big one that shows when you go back to the title screen) then it should have worked no matter what came after that.