I didn't really read up your entire post but Rufus has NTFS drivers to make USB sticks UEFI compatible, obviously for wims or any file larger than 4GB, then no need to split (SWMs).
Code: Important Windows Setup doesn't support installing from a split .wim file for Windows 10. So Microsoft are lying or have no clue! They should employ murphy78 ASAP
I still wonder if there's a way to fool this with the boot.wim or iso layout... I tried a few things, but I never really dug too far because I already had a working solution. I remember previous Windows versions having a licensing folder, but I think I tried that and it failed, at least during boot setup. I think I also tried shoving them in the boot.wim index 2, but I don't remember. Sadly, I've lost a lot of interest in figuring out these kinds of things since I no longer torrent.
Just to add, the ei.cfg that you mentioned in OP - that's added so that windows doesn't prompt for a key when installing.
It is. I do all my installs from a usb3 key. It's also easy to add base drivers on the fly using dism too: Code: Dism /Image:W:\ /Add-Driver /Driver:%Drv% /Recurse /Forceunsigned No need to integrate any drivers to wims/esd's anymore. Easy to keep updated...