0.) Make sure the difficulty in which you want to use another MP3 is already made. Put one note anywhere.
1.) Put the other MP3 in the folder containing the mapset.
2.) Open up the .osu file of the difficulty to change the MP3 in a text editing software (e.g. Notepad)
3.) In the AudioFilename: , replace the string there with the filename of the new MP3.
4.) Go back into osu! and edit away
AFAIK this should work.
1.) Put the other MP3 in the folder containing the mapset.
2.) Open up the .osu file of the difficulty to change the MP3 in a text editing software (e.g. Notepad)
3.) In the AudioFilename: , replace the string there with the filename of the new MP3.
4.) Go back into osu! and edit away
AFAIK this should work.