Prohibit modification, when importing from an xml data source
I have a FMP file to manage my music, into which the songs have been imported from iTunes with an xml/xsl style sheet, with a little help from friends.
I update the FMP file, to get the recent additions to iTunes, also with an xml import, matching the existing songs and adding the non-matching songs as the new additions.
This works fine.
But I do not want to re-import all the information of the matching records, as I made changes in my FMP file (Why else make a FMP file if you have iTunes)
So I checked in several field definitions - of the fields i did not want to be overwritten - the box "prohibit modification of value during data entry" .
Still, the data of these fields in the matching records were overwritten during an update run.
Doesn't the box "Prohibit modification" work, when importing from an xml data source?
Is there any other way to prohibit modification?