Yes, that is what I am suggesting.
I would see if I could figure a way to use ForEachObject to get each door. If the custom record is already attached, then just copy the field from the Door PIO and store it in the custom record. If the custom record is not attached, then attach the record and copy/store the field.
You would copy and store the fields using the GetRField and SetRField commands.
You can use the script in the thread below to see what the record and field names for the Door PIO record need to be.http://techboard.vectorworks.net/ubbthreads.php?ubb=showflat&Number=108487#Post108487
If you want to do all the doors in the file, it will be pretty easy. If you only want to do some doors, you will need to figure out a criteria to identify the ones you want. Maybe manually attach the custom record and then only process the doors with the custom record.
Ask again if you need more information.