A Virtual Machine adds an unnecessary new layer of complexity to the usual procedure, but to try to fix your issue, please try the following:
- Revert back all changes
- Boot your 10 OS in UEFI
- Make sure your (UEFI) menu.lst is located here: \EFI\grub\menu.lst
- Run BootIce and open UEFI Tab, there you will be able to see the actual predefined boot file used by the UEFI firmware of the virtual machine (this info is stored on its NVRAM).
- Now make the renaming and addition of files in accordance with the info you got from BootIce UEFI Tab.
- Edit your menu.lst as required see following quote of my menu.lst as a guide, NOTE: It has to be UTF-8 without BOM (use Notepad++ for this).
- Reboot and all should work fine now.
JFYI: On same UEFI BootIce Tab you can edit the actual values, or add additional boot options but this may require to use the respective F key (usually available on real PCs), doing this is very usefull for our USB devices.
menu.lst
title Windows EFI BootManager - chainloader /EFI/Microsoft/Boot/bootmgfw.efi
find --set-root /EFI/Microsoft/Boot/bootmgfw.efi
chainloader /EFI/Microsoft/Boot/bootmgfw.efi
title Windows EFI BootManager - chainloader /EFI/Boot/bootx64_win.efi
find --set-root /EFI/Boot/bootx64_win.efi
chainloader /EFI/Boot/bootx64_win.efi
Hope this can help you to solve the issue.
EDIT: I'm using so far G4E Build 2021-02-10, haven't updated yet to the last version.
alacran