People listen!
data/users.txt is not related to ULib/ULX in any way.
data/ULib/users.txt is ULib's users file.
settings/users.txt is the default GarrysMod users file.
* [REMOVED] Old settings/users.txt stuff, handled by SetUserGroup now
The old method of importing admins from settings/users.txt (by reading the file ourselves and adding the users) has been removed becase it is now handled by SetUserGroup when garrysmod imports the file.