1. Setting Up Your osu!mania Map - skyewontmiss/ExtendedCharts-For-CSharp GitHub Wiki

First thing you'll need to do is go and grab osu! from osu! by Dean Herbert, and download osu!, NOT osu!lazer. We haven't tested osu!lazer with our systems yet.

After that, open the game and (preferably) you should log in, as osu! will autocomplete the 'Mapper' field if you do.

Anyway, click 'Edit':

And drag in your .mp3 to this field:

After that, you will be taken to this screen, and this step is now REALLY important.

Up here, click 'Advanced', and it should be like this:

Click the dropdown, and set it to 'osu!mania'.

Then, go to the 'Difficulty' tab, and to the 'Key Count' option.

Now, drag the slider until it is set to five. It is INCREDIBLY important you set it to five, nothing more or less, because the game will not be able to recognize other KeyCounts yet. (unless we fix it. In which case we will update this guide if Skye remembers.)

Great! You're all set. Now, go to the 'General' tab and fill out these sections...

Do note that it doesn't matter what you call the difficulties in osu!, as Poly Beats makes you confirm these in the importer. Alright, you're set up! Just click 'OK' to create the map!

...I'm not going to teach you how to map in osu!mania. There's plenty of tutorials to do that. osu! themselves explain it better than us. Here you go: The official osu.ppy.sh osu!mania Mapping Guide

Alright, when you're done, skip to the next section!