1. In the elevator stage, I tend to jump on the top-most platform right after the second elevator. At what level do the elevators descend too quickly to pull off this move? In a point-scoring game, does it matter if you make that top jump?
Never, but it's risky and not really worth doing unless going for a top 10 score.
2. I noticed there are three patterns for the springs. Is this throughout the whole game? I always thought there were just two. One that will always hit you, one to climb up the ladder safely.
See the Spring Theory thread. Springs have 16 different lengths and several long springs in a row can occur.
3. Not really an elevator stage question, but it tends to affect me here. On the arcade cabinet my friend and I use, sometimes after letting go of the joystick Mario will keep moving... and walk off the platform. Is this a problem with the machine or something we have to learn to deal with. (How?) Your joystick is gunked up, needs taken apart and cleaned.