This article lists the various ways to import songs into Interlude.
In Options > Library, you can link your existing song libraries from osu!mania, StepMania, Etterna or Quaver.
To save disk space, your chart files will be converted to the .yav file format, but the game will still load the audio and background files from the original location.
This means if you later move or delete that game's songs folder, Interlude will no longer be able to find the audio or background files for them.These links can be set up to automatically detect any new songs added to your linked games when you open Interlude.
Import new songs from the internet
You can import Etterna packs and osu!mania songs ingame (similar to osu!direct) through the options menus or by clicking 'Import' in the top left.
Import new songs from files/folders on your computer
You can also manually drag and drop .zips, folders, .osu files, .osz archives, etc onto your game window to install them.
Not sure what to play? Tables are hand-picked sets of charts, organised by difficulty so you can progressively work up the level ladder and improve your skills.
On the Tables tab in the import screen, you can download a table.
Currently, the only existing table is Crescent, which has a wide selection of 4K charts to play