I'm experiencing what seems to be a bug related to RC4's detection of an "off-track" condition when the GPS is used for "own nav." Here's the scenario:1. After "resume own navigation," use the GPS to manage heading - GPS/Nav switch in the GPS position and enabling Nav on the autopilot. The GPS and autopilot nav function will manage the track according to the loaded flight plan.2. Use RC4's "Dir Ckpt" feature (on Next menu from main screen) to select a future waypoint for direct-to clearance and receive requested clearance.3. Use the GPS to activate the flight plan segment beginning with the direct-to waypoint (intersection or VOR). (On the GPS, click FltPlan button, press cursor knob, then use outer knob to move cursor to first waypoint beyond the direct-to waypoint. Press GPS Menu button to get popup box offering to activate segment beginning with direct-to waypoint, then click Enter to confirm. This will move red bracket to segment that begins with direct-to waypoint.)4. The GPS will now navigate a great circle route from the present position to the cleared direct-to checkpoint, which will likely bypass many original airways and waypoints, which was the objective of requesting the "direct-to" clearance.4. Soon after the GPS begins managing the great circle route to the direct-to waypoint, RC4 will respond multiple times that the aircraft is "off-track," with the controller becoming increasingly irritated by the seeming disregard of the original track.5. Bottom line, RC4 does not recognize that the plane is following the direct-to clearance along the great circle route generated by the GPS.6. Another small bug during this process: if the list of waypoints on the RC4 "dir ckpt" screen overflows to the next screen, you must press 9 to see the remaining waypoints, though on the initial Dir Chkpt screen, the "Next-9" option does not appear as it should.Doug HortonP.S. Example *.pln file and direct-to requests available.