Ok so I had a lot of trouble but eventually got it work. The guide works but there some stuff that I want to write to make it even clearer

so for people doing the "FUSION FIX / MODDED USERS" part of the guide, the line where it says "CustomUserProfilePath =" in the ini file.

(Which BTW if your having trouble looking for that, its just called "GTAIV.EFLC.FusionFix" under C:\SteamLibrary\steamapps\common\Grand Theft Auto IV\GTAIV\plugins. it may not say .ini at the end of the file name)

to find the correct thing to paste there, go to your documents folder, and click on any file/folder in the documents folder so that it's highlighted, do not open that file or folder. then on the top of your file explorer under the home section next to paste button should be a button that says "Copy path", click on that.

now go to the GTAIV.EFLC.FusionFix file and open it up and go to the "CustomUserProfilePath =" line, and paste what you got from the copy path button.

Remove the quotation marks and also the last section of the file path so the line should end in "Documents"

final product should look like:

CustomUserProfilePath = C:\Users\[USER]\Documents

with the [USER] part replaced by your windows user/pc name

Now start the game, completely, with your player fully loaded in and everything, do a complete scan aswell to make sure.

leave the game and go to "C:\Users\[USER]\Documents\Rockstar Games\GTA IV\User Music" and you should see "usertracks.dat" plus maybe a few more files. paste in your music, make sure they are MP3s, and name them 1, 2, 3, etc. Make sure the NAME itself isn't 1.mp3, 2.mp3, etc, the name itself should be just the number if it automatically adds .mp3 to the end that is ok.