I had the same problem when trying to select an approach int KPSP. After adding waypoints manually i figured out why it wouldnt add the whole approach. One of the waypoints was "not found in database", even tho it is in the airac, i even double checked the file to see if it was there. I have no idea why the plane wouldnt accept it tho. This unfortunately causes me to fly my other paywares more often than the cs757 :( I hope somebody figures out why this happens, if its possible to fix without a service pack