NTRX Trackmania Hub

Trackmania United Forever

1. Go to the documents folder.
2. Locate the TrackMania folder.
3. Go to the tracks folder.
4. Access the campaigns folder.
5. Paste both the folder and the GameCtnCampaign.gbx file into that directory.
6. Profit!

Trackmania Nations Forever

1. Go to the documents folder.
2. Locate the TmForever (standalone) folder OR TrackMania (Steam presumably) folder.
3. Go to the tracks folder.
4. Go to the Challenges folder.
5. Go to the Downloaded folder.
6. Paste the folder or the folder contents in there but NOT the GameCtnCampaign.gbx file
7. Profit!

If what you've downloaded only contains a .gbx file or that there's no GameCtnCampaign, put it in the "Downloaded" folder (it's in the Challenges folder)!