I successfully created a multibootable USB using WinSetupFromUSB, allowing me to boot into an ISO for MS-DOS 6.22 and installer ISOs for Windows 7 32- and 64-Bit from a single bootable USB. However, while the Windows 7 ISOs are both accessible from the Windows Boot Manager (bootmgr), MS-DOS requires grub4dos to be loaded.
This means that my bootable USB is split into two separate boot menus; the grub4dos menu, which is initially booted into and contains the menu entry for booting into DOS 6.22, as well as another two (first and second half of Windows 7 installers) for booting into bootmgr, from where both the Windows 7 entries can be found.
I don't like this way of doing things, and I'd really like to unify all four entries into one single menu under Windows Boot Manager. Is this at all possible?
Thanks in advance, I really appreciate any help I can get. I also have a related thread on getting DOS 6.22 to work with a bootable USB over here, and would appreciate expertise on that too: