FMS Crash Changing Cruise Alt

Hi, Further to my post here: http://forum.avsim.n...ost__p__2048771 I had to abandon my first attempt at this flight as during the climb out ((I was heading towards DVR5 waypoint) I altered the cruise altitude on the CRZ page from FL360 (entered before takeoff) to FL350 by entering "350" in the scratchpad and entering it in the appropriate line in the CRZ page (CLB was active but level at 6000 ft). I had just increased the altitude on the MCP from 6000 ft to 13000 ft prior to the change in the FMS. The aircraft was still level due to altitude restriction. After the update, the FMS data fields that should have re-computed/updated just went blank. The entire sim crashed, though the aircraft kept flying. I quit FSX and restarted it. Best regards,Robin.