Thanks. Our NAS is very fast and we have not had problems! But we will store the programs on the local machine. If the music is not processed through the library, does the repetition protection of tracks feature work?
Yes, repeat protection (for Track List or Playlist Generator) works regardless of music library.
NAS is slow when you have lots of small reads - that is, reading tracks information when preparing categories for playlist generator can be up to 1000 (thousand) and more times slower than reading from a local drive (especially if it's SSD). But you should see how it works on practice, and you can also utilize tags caching that mames things faster: https://manual.djsoft.net/radioboss/en/tag-cache.htm
General recommendation is: configure everything as you need, then if you see any performance or other issues, deal with them, as it's hard to predict what can go wrong.
Some users with NAS complained that creating a playlist using music files stored on NAS can take more than one hour, while it's couple of minutes if the music is stored locally.