This is my answer to all the hype surrounding the new Serato STEMs implementation. Rows 3 and 4 of Banks 1 use a combination of Instant FX and Neural Mix to achieve a similar result to what Serato is doing.

Please use the Midi Fighter Utility to enable 2 Banks mode on the MF 64 so that you have access to the Looper functions on Bank 2.

Most buttons have a Shift layer and are shown in Orange in the mapping key.

For the Neural Mix Instant FX 6, 7 and 8 you can select your own options for Drums and Vocals within Djay using the pencil icon at the top right, but these are the settings that I found work best: