Keep your user folder empty so you can use it again and again. Copy the user folder inside your C:Program FilesDAZ 3DBryce7PresetsObjects folder. Paste it and the computer will call it "copy of user". Click on tthe folder and rename it something. Ive created Christmas, egypt, pirate folders this way. Open the renamed folder and you should see a user.obp file. Rename this as well to Christmas, egypt, pirate etc. You could even copy and paste several obp files and name them. That's how you get several categories in the same folder. You could set up ornaments, presents, text, inside christmas for instance.

The thing about bryce material and object files, once you import the object stays in the file. If you delete it the name and path get removed but the object stays. Once you bloat up your directories by adding and removing things it slows down how fast they load and display. If you export and import the empties get left behind in the old directory. Keep an empty so you can prevent file bloat.

Here's an old tutorial I did on material folders that can help.

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2704027