If you have setup FT Grenadines correctly with autogen and your default.xml is not corrupt it is still possible that Autogen is not working.
In my case, I have found the culprit to be the file: OLC_NA_REG.bgl located in the ORBX FTX_OLC Scenery folder.
I have switched it off and my autogen is 100% ok.
I am still testing and have not found any issues yet.
Will report back if I find some.