How to open Traktor Stem mp4 in Abelton as separate tracks.

If you're opening a song via drag n drop from the traktor browser, you will get the original file, even if you have created stems for it.

You need to open the multistream .mp4 file from the stems folder, after playing each one (because they're named with short codes for filesystem efficiency) to see which one corresponds to that song. But still, Live 11 doesn't support multistream mpeg audio files (I don't know about 12 cause I don't have it installed).

You can always drop the .mp4 file in Audacity. A dialog will popup asking which stream you want to import, and from the 5 streams, the first is the full track, the rest are the stems. So you will need to save the stems in separate files first from Audacity and then you can do what you please with each one.

If you want less hassle but the same stem algorithm, you can always buy Izotope RX 11. Or if you don't mind a different algorithm which is also quite good, there is a Demucs GUI on fosshub, there are also plenty of other paid programs like Simple Stems, or you can use one of the hundreds of sites that offer stem separation online.