Spoiler: Starting Work the bottom layer first Spoiler You need to work one side on the way up and the other side for the trip back down.
Spoiler You need to anchor your motors. The first assembly popped right out of the structure, so I dragged it over the win.
Spoiler I hadn't thought of that as a solution. It's an interesting and ultimately valid one. However, that troublesome piece was made without a motor. I added the column above for extra stability. It was actually made with sunken metal pillars. When I was testing it myself, the column seemed to stop the piece from popping out. I may take a moment to make a more stable version with a motor. Aesthetically I like the smoother motion without the motor, compared to the motorized piece on the roof. Thanks for the feedback.
You had the right idea. Free draggables are generally to be avoided because they aren't governed by the physics engine and are literally "free" to be dragged anywhere. This makes them "cheats" since they allow players to ignore the intended spirit of the game. In your case, you used them for a purpose no other block could fit, you just didn't lock it down tight enough to prevent their unfortunate side effects.
Since I seem to be on the right track, any suggestions for locking this thing down and allowing it free rotation?
Can you do a letter H configuration? That would give you horizontal movement and could be contained by putting stopper blocks "inside" the arms of the H.
