You could create separate NX roles (*.mtx) and then set the variable UGII_DEFAULT_ROLE to point to the respective role based on the user's environment.
# This variable defines the default role that NX will use at startup time. # If directory path is omitted then the system will look for the specified file in the NX/Open roles directories. #UGII_DEFAULT_ROLE=advanced_full_menus.mtx
If you want to point your users to specific edited ribbon files (*.rtb) place these in an application sub-directory pointed to using one of the variables defined in the documentation here. For example:
Place the .rtb files in X:\directory\application
The custom ribbon files will be read on startup.
More information here: Customizing the NX interface using files