Actually, two questions.
Can I make a screen other than screen 81 a 3-stair warp?
And how do I tell which stair goes where in a 3-stair warp? Or is it random?
3-Stair Warp Question
1. I don't think so.
2. The staircase on the left takes you "back" one warp, the middle staircase takes you between two places (if you go in the middle twice, you'll end up back where you originally were), and the staircase on the right takes you "forward" one warp. As in, if you enter either the left or the right staircase 4 times in a row, you'll cycle through the four warps without seeing one screen twice (within four warps).