Moving library from BluOS to MinimServer and tagging

[ClassJar]

Hi all of you in this forum. I have a fair size of music library in my Bluesound Vault 1 and I have a plan to move it to synology NAS in MinimServer. The reason for this is to get album infos better and get better searching, because I listen 99% classical music.

If some of you have allready done something similar, please advice me in this. What would be the best way to do this all IF...

1) There is about 20000 songs/tracks in FLAC, some of them labeld as unknown by
Bluesound. Is there a way to get all metadata/info updated automatically, at least
most of it.
2) What would be the best way of moving those files from Vault to NAS? Direct copy or
would it have more reason if they are moved in smaller chunks?
3) Can this all be handled with Minimserver or do I need some other software too?

Thanks allready for replys.