The Y-Axis State Machine was getting "corrupted" when positioning any Axis higher than 3. The machine index stored in the state machine was getting corrupted which ultimately resulted in Axes with ID's higher than 2 not positioning.

What was actually happening is that the size of the Array of state machines was defined with one literal variable which was too small. The array bounds checking was being done with the correct literal. Any Axes with an ID higher than 2 was using memory that it didn't own, which resulted in it eventually being "corrupted" by the actual owner.

This has been resolved.