CXs are always tricky Set position in the city and it will work
NTU + small CX wont work.
It cant work coz with MMR file you add EPM to your existing NT map, if you dont have NT it cant work, it's like you would like to use a part of a map without having that map .
Edit:
Check the Full CX map with gmaptool, you'll see the subfiles inside, MMR are just a part of the map, other files are present in CNEU NT map, so useless to have them twice, but if you have NTU, you dont have these files coz in NTU are different,so must load the full CX map with all the subfiles.