Not having any issues with mine at the moment, but this is what i do to start it up.
1. Open the motion in joy program
2. plug the control in
3. go to driver manager and select "Load driver"
4. go to profiles and select a mode ( i usually select xbox 360 controller emulator)
5. click "Enable"
This works for me...
I dont have assassins creed on pc but this worked for street fighter and also my DS emulator, but if it picks up on one game it should pick up on all games that support xbox 360 controllers.