It appears to be in my Scenery.CFG. I haven't edited by hand, I use the FSX Scenery Manager. I've attached the file.
I think the problem is the "remote =" line in the Area 334 ( Aerosoft Barcelona X ). Having a key without a value in an .INI file is usually considered an error, and so the parsings stops there.
FSX uses a more tolerant custom parsing routine, so it's able to accept some formal errors in the scenery.cfg, but GSX uses a standard .INI parsing method, which means the file must be syntactically correct. You should be able to fix the problem by removing the orphaned "remote=" line.