Using the FSX data for Gates at Los Angles KLAX I place my 737 at some of them and the CDU says that gate is "not in the database"Where can I find a list ofr gates in the PMDG 737NGX compter's database?Thanks

That GATE field on the FMC POS INIT page is only for use in aligning the IRSes - the NGX has GPS however (go to page 2) and it makes the gate coordinates superfluous. In the case where the navdata includes gates, they're the real life gates, not the ones in FSX's default scenery. (which rarely match the real life names) You'd have to look at the airport's actual charts to see the real gate names/positions.

There isn't a database already made, though someone with a little programming experience could make one. You can find it yourself by using the search function (make sure to include the contents of each file in the search). Search "FSXPMDGSidstars" for "Gates." Every airport with gate positions for you to use will show up.