I don't have NXG personally, but you might check the installation folders for the UserTags folder, like how Darren describes.
For example,
C:\Program Files (x86)\National Instruments\LabVIEW NXG 5.0\vi.lib\UserTags
(This assumes a Windows heirarchy and a 32-bit installation.)
(Also, I did say I don't have NXG, so the folder "LabVIEW NXG 5.0" might not exist. Or something.)
If the folder isn't there, UserTags may be implemented elsewhere in NXG, but not in the same way.
(I have seen in passing that NXG has a native "Tags" feature...is that the same thing? Please excuse my inexperience. 😁)
(And I sincerely apologize if this post is a waste of your time.)
-joeorbob
