When using the system with EF lenses or stills glass that does not have hard stops you will need to 'fake stop' the gear on power up.
1. Unmesh the motor from the lens gear.
2. Power up the motor.
3. Physically grab the motor gear to stop it turning.
4. After a few seconds of it turning the other direction stop the gear a second time.
When rough fake stops have been established you will be able to mesh the motor onto the lens gearing and access the 'Manual Recalibration' setting in the Controller Menu to set more precisely where you want the actual lens stops to be.