Thanks, everythings working now! In the ASET folder in GameData there is the ASET_Props folder and another GameData folder which actually has the correct files including the MFDs file and lots more. So I just replaced the ASET_Props folder with the one that actually contans all the files, weird.
(Simplified problem with the file directory) GamedData>ASET>ASET_Props(with lots of files missing), GameData>Aset_props (with all the files needed)