I've actually gotten this to work, here's what I did:
Extracted sd+mmc_generic_driver.7z
Changed to starttype = 0 in all inf files
Deleted sdbus and sff* from driverstore (you have to do this otherwise it will bsod after second stage)
Used DISM /add-driver (Not DISM++, that did not work) to add the drivers into windows 7
Enable Testsigning
Windows 7 will then boot, but it will refuse to have any pagefile for some reason. It will bug you about that every time you log in. Also no write caching.
This works on Braswell and GeminiLake, doesn't work on BayTrail.