Very nice and neat mechanisms! I like the wall and room power of each card. Perhaps for the advabced game, there is a certain limit to the use of wall and room power.
The example in the rule book seems to kook like a rotation effect when the central card was replaced. But the rule states it is just one to one replacement.
Besides a solo game, it can be a multi-player solitaire with the same starting cards. Whoever meets the objective first, wins.