i doubt people familiar with the legal /business relationship details between warp and afx will post here.

most of the release you talk about are from the 90's. theres old interviews where richard talks about being able to release his stuff on his own label with the blessing of warp, probably it's just goodwill between him and them, many other musicians had similar deals, being able to self-release the excess stuff they produced on smaller labels you can clearly hear that the quality, polished forward thinking stuff was developed and saved for warp and the rephlex stuff was older, rawer archive-level stuff that wouldnt cannibalize the sales of the releases that were $marketed by warp.

korg tracks were released on bleep store, warp surely gets its cut, whatever that deal is.

the story is that the gak tracks were sent by rich in 1990 as a demo to warp who rejected them at the time, then the tracks were reconsidered after richard signed a deal and became popular and a good record seller.