I am pretty interested in getting one of these, sounds like a nice simple setup for large scale projects. When you test in open loop (not mechanically connected), if you play with the trims on the remote until the motor starts moving, can you confirm the direction you have to move the pot to stop the motor movement corresponds to the direction the motor turns?
Regarding pot wiring, there is a cursor on a pot, that is the wire attached to the piece moving across the resistor. If you have a larger pot, usually the cursor is the center pin. You should be able to confirm with an ohm meter (tester set to resistance testing). The cursor is the only pin that will show a varying resistance between it and any of the other two pins.
If you test the resistance between the two other pins (not the cursor) you should read a constant resistance nonmatter the pot position. Once that all tested you should know for a fact which is the pot cursor.
If you have the documentation of the thor 15 it probably shows where the cursor should go. But then again, if you have a proper response to your input on the pot it sounds as if it is wired with the cursor at the right place. I would triple check the pot direction of rotation to make sure it provides a feedback in the proper direction.