Two graphical fixes and one minor improvement

I thought I might not come back to it, but it turns out that it's probably not all done yet. While trying to adapt the game for SAA sound for SAM Coupé a while ago, I noticed some new possible improvements and fixes for both computers.

Two graphical errors regarding lifts have finally (hopefully) been completely fixed. Mario riding a lift now always appears at exactly the right height, the gap between Mario and the lift is always displayed, and the lift never colours Mario.

The monkey's open mouth looks better during the fall, just like in the arcade version. After the fall, the monkey has a different mouth and eyes shape, similar to the arcade version (it can still be improved).