This 'guide' is meant specificly for courses that are downloaded,
not those that you are trying to create. Courses are also sometimes referred to as marathons. Survival and Oni courses are also used this way.
These should more or less be the folders in your StepMania folder.
Right now we're only focussing on one of them - Courses.
This is the basic folder structure that your groups on songs should be in.
In this image - Courses being the base directory,
WinDEU being the group directory.
The Group directory may be named literally anything
excluding symbols which computers don't allow.
These are the two files involved with courses.
The *.crs file is the scripted song set and modifiers (if there are any).
The *.png file is the banner for the marathon. May also be JPG. Should have the exact same name as the *.crs file it is related to.
Q: Scripting mods?
Different FAQ for a different time.
Q: Some of the songs are not showing up when I select the course. Why?
Two possible reasons, the first being the simplest, maybe you don't have the song. Get it. If that isn't the case then the song is not referenced properly (or specifically enough) in the course for your setup. The #SONG:::; tag in courses can specify a song using only its song title or go as far as to map the layout of the folders and include the author of the song. Specifically, if you have multiple simfiles who share a common song name that is used in a course, specify the folder layout, generally that's all you'll end up needing to do.
Example! #SONG:VirInPro/wDEU/Chik Habit:HARD:;