I recently dissembled and transported a treadwall from an apartment complex's gym to my house. I will say that it is not the easiest task, but with a little mechanical skill its not terrible. I actually hired two guys from a gym equipment repair company. While they had never worked with treadwalls before, the size of the unit made it necessary. The whole process took us about 4 hours. Instead of disassembling the machine standing up like the breakdown checklist shows, we tilted the whole machine forward onto the front arms after we took the climbing surfaces off. Having the machine laying down helped greatly. While we did not have to completely take it apart, most of it does need to come apart to transport. When disassembled the climbing surfaces all fit in the bed of my truck, and the rest of the frame and parts fit in small trailer. I know I'm a little late to the game on this post, but hopefully it helps somebody in the future. Feel free to PM me with any other questions.
We moved ours by taking all the way apart- although the core frame can't be disassembled, so there's this big piece that ends up being a total pain to deal with. Ours is older, though, so they may have changed it since then.