OK! Thank you very much for yours explanations!
You are welcome.
Program, or what's on the USB stick has no such control over BIOS, if F8 boot menu starts USB, whether stick was prepared with 0.2.3 or 1.0 betaX should not matter, it should boot or not the same way in both cases.
I am 100% sure With WinSetupFromUSB 1 Beta 8, I no need to Force USB Drive in Bios. Just Select the good USB Drive Once with F8 BBS Boot Menu.
With WinSetupFromUSB 0.2.3 I have to Force USB Drive for Working.
I'd love to prove you wrong, but can't, I have no such hardware around.
For the Verbatim key problem, could we not use the minimised batch "setup.cmd" to simulate a "disconnect-reconnect" of the USB key?
Setup.cmd is launched before real Setup starts, for GUI mode, like in T-0, or T-(-1).
It does some things, launches real Setup and is closed. The only leftovers are the minimized CMD screen which should keep the USB drive letter untouched during Setup using 'pushd' command, but in your case it does not. There could be another solution, never needed such until your report, after more than 2 million downloads of the last few versions.
To simulate reconnect at the right moment, and that seems to be at T-28 according to your report, a program must be monitoring the USB key the whole GUI part and if it's lost, then reconnect it. I am not even sure if such program could survive, or run in background the whole GUI part.
It's more interesting why the USB drive is lost, with this particular USB stick...
Can you try something- on installed XP, which never seen this stick, plug it and let it detect it and install drivers. Does it ask for reboot before the device is ready to use? If yes- does this stick have some extra features, like encrypted part of it, CD/DVD part or something unusual?