09-21-2011, 04:59 PM
Oh wait, I'm having the same thing on my system. For now, I think you can get around this (and launch your paid-for version) by deleting your preferences file in
home / LIbrary / Application Support / ActionSoft / Midnight Mansion HD / Midnight Mansion HD Prefs
home / LIbrary / Application Support / ActionSoft / Midnight Mansion HD / Midnight Mansion HD Prefs

