Gate assignments

Never had any problem with FSCommander flight plans but now with PFPX it exports the .pln file with no gate assignment.  I end up going into the file and manually inserting the gate before opening.  When you load your plan and it asks if you want to move your acft to another location you click "yes".  I then click the location again and change the location to a gate instead of the runway that was input  with the flight plan.  The problem is that I can't click on start flight... it is greyed out.  If I tell it to find route it gives me an entirely new  FP.

Been simming for years and never had this problem.  What's up?  Any ideas?

Jeff