Sanctum: Don't save sanctum until next room is chosen!

Idk mb I've got that wrong, I like to complete room at first (that disables traps btw) and then open chests and farm mobs but now I've got disconnected and voila - I'm starting with next room, so I can't pick up my reward for completing a room. I'm glad that it was just a fountain room but imagine if there was a mirror, huh? I'd delete the game immediately if so.