Seems that Xorg is heavy user of udev. Probably USB stics etc removable media need udevd (mdev is some kind of static brother of udev).
udev is "child of Unix", use to be small at first, gigantic piece of code nowdays.
These constant installation problems with Xorg are probalby related to that Xorg special udev use. Should be static process at boot, dynamics should be for USB etc. only.
Should be like this:
a) TC BusyBox/Xvesa system on USB-stick. Lets name it as "Pelasti". It is not just rescue stick, but installation and maintenace stick too. TC main numbers (5.xx, 6.xx ...) needs new Pelasti, same main mumber (X.01, X02, ...) just update drivers
b) Target installation with Xorg (maybe with Gnu utils) on HD or/and flashdisk with drivers installed. Removable media (USB), needs set of drivers. This is not problem, because USB-driver is two-layer, only need upper layer drivers.
c) Target drivers installation have to be done two times (second time just Xorg-drivers)
d) If TC installation prosedure could support this interactive udev "device driver loading at installation", EVERYTHING would be easy
e) Becouse TC is not supporting this genius interactive process, I have to do it manually: lspci, lshw, udevadm, read_EDID etc. set of tools must be loaded on Pelasti. With some digging /dev /sys directories may be enough to save world
This not necessary solve these problems with Xor-drivers, but lets try...