Don't worry guys, I've sent a fix in to Vern and he'll release an update of the game (1.0.1) shortly (like sometime this week, if I recall correctly). Hold on till then.

The problem seems to be that although behind all the other yellow doors on the left (brick) section of the mansion there's a yellow key, there's no yellow key behind the yellow door in room 14701, and the yellow key behind the yellow door in room 14499 cannot be obtained until all the doors in room 14897 have been opened (not just the red trapdoors, but the gray doors as well) and the elevator platform can descend all the way down to room 15097. Also, until this platform descends, you cannot get the second blue key in room 15097 nor the second purple key in room 15099 necessary to reach the upper keep and go around to open all the gray doors in 14897.

However, it is possible to complete this level. The trick is twofold:

1) Avoid opening the yellow doors in rooms 14499 and 14701 until all the other yellow doors in the left (brick) part of the mansion and their sections have been completed. Remember to save the yellow door in 14701 for last!

2) You can obtain the needed second blue and purple keys in the right part of the mansion (dirt and snow), so I recommend doing this side first. You'll need these keys to open the doors in room 14700 to reach the upper keep. Just whatever you do, DO NOT use up the purple key you obtain at the right (dirt and snow) summit to open the door in room 15105. Instead, finish the left (brick) part of the mansion first and then return to 15105.

I'm still having the problem with the sticking bat platform in version 1.0.1. Is this part of the game play or a bug? 

I'm going to download it again and give it another go.