If you're having issues with NSM, try switching to
http://neurosdbm.sourceforge.net/.
It doesn't keep a database of everything on the computer, you just use a file open dialogue to pick the files you want on the Neuros, and it'll copy them over and add them to the database. You can also direct-edit the entries yourself (Does not change the file tag, does change the entries in the menu), or hand-copy the files to the Neuros and effect a "Rebuild".