so, in fact if you run the DB in the DBAirnav Syst Editing program, decompile it in excel files, make a copy of the "old" Airport excel file, then run the updater on the DB file, and again edit it with the editing program, replace the "new" airport file with the "old" one, and recompile a new DB file, ...... everything should be ok.
I already do this for the Airlines part, so I can keep changes I made to the DB.