CDG ZIP Support not recognizing the Mp3+CDG pair.
Because MP3+G is stored in pairs, the pairs are often stored inside of a zip file. People have been doing this for years in order to keep the .mp3 file and the .cdg file together... So inside of the zip file you will find two identically named files - just like you would with a normal mp3+G but it's zipped.
VLC will open the zip file, but will play the mp3 first. Then it will play the cdg file. It does NOT play them together and this is a bug. It should check the zip file if it contains any files with the exact name and should play them together - not separately.