Hmm... I had a look at the file and found two errors:
- The connection from 126 to 129 must be removed; bots tend to fall down there.
- The connection from 296 to 0 doesn't work; bots fall down. Try making them step onto the roof by going straight forward, over the opened "door" in the roof. The distance sideways is too big; they fall down before they reach the roof.
Concerning the elevator, I got it to work in 60-80% of all cases. However, there's something wrong with that lift. It kills bots! I saw many bots enter the lift, push the button, wait for the lift to arrive and get killed suddenly.
I suppose the only way to be safe is to leave out the lift. There are enough ways to reach the rooftop anyway.
Oh, and you're not too familiar with that apmd feature yet, are you?
Looks like you hardly used it so far... it took me some time to get accustomed to it, too.