Large number of pictures on a NAS - Where to install program?

[rumo]

My pictures (about 140'000) are stored on a NAS so that i can work with them on several Macs.
- Where should i install the program? On each Mac or on the NAS (in the Folder of the Pictures)?
- If i copy the Folder with all pictures to a security-disk: Does the catalogue still work?
Thank you for your help.
Ruedi

[xnview]

- Where should i install the program? On each Mac or on the NAS (in the Folder of the Pictures)?

On each Mac, perhaps better.

- If i copy the Folder with all pictures to a security-disk: Does the catalogue still work?

I don't know, you need to make a test...