Summing up all these, it seems like the only foolproof way to have a "universal" USB stick would be to *somehow* mix the Rufus UEFI:NTFS driver with *my* (or similar) approach to boot through BIOS off GPT partitioned device, adding additionally Clover (or ReFind or similar).
This way the device will be "fully" GPT (but still remain bootable on BIOS) allowed to host bigger than 4 Gb images, and if by any chance forced into CSM mode, returned to a "volatile" UEFI environment through Clover.
I have used 'GPT partitioned scheme for UEFI' option in Rufus to create UEFI Bootable Removable USB Drive. Now my Removable USB have two partitions. First NTFS partition contains all Windows Setup files and second small FAT12 partition contains UEFI:NTFS driver.
After that I have tried to implement Wonko special method described Here
C:\GPT\mkhidGPT.cmd
C:\GPT\FAT12grldr.bss
C:\GPT\HidGPT63.mbr
C:\GPT\dsfi.exe
C:\GPT\dsfo.exe
C:\GPT\mformat.exe
C:\GPT\mmd.exe
C:\GPT\mdir.exe
C:\GPT\mcopy.exe
C:\GPT\root-
|- grldr
|- menu.lst
|- BOOTMGR
|- boot-
|- BCD
Where 'menu.lst'
map (hd0)63+1985 (fd0) map --hook root (fd0) chainloader /bootmgr boot
Running 'mkhidGPT.cmd' at Windows 10 with elevated permissions
C:\GPT>mkhidGPT.cmd myimage.img 1
A proper MBR and sectors 63-2047 are written.
Windows booting from BIOS at GPT disk does work. Grub4dos loaded and chainload to superfloppy 'Bootmgr' and 'Bootmgr' finds (fd0)\boot\bcd. But After that I have to face Windows Boot Manager Error Messages ???
Status: 0xc000000f Info: A required device isn't connected or can't be accessed.
What should be boot sequence after this step ?
Am I missing something ?
What should I do so that I can transfer boot control from super floppy 'grldr' or 'bootmgr' to Removable USB Drive '\grldr' or '\bootmgr' ?
..'cdob' ! Have you tried 'Wonko' approach in USB Drive ? Anyone Please...???
Regards....