Ok, I’ve built the default Grub2 and that one also halts with a bar cursor, so something is wrong in the build scripts (or something extra needs to be done). I’ve also build an x86_64 Grub2 from the sources available at the GNU website and following instructions available on the internet I managed to get it done. After installing that version of the BOOTX64.EFI file I got the same results.
Could it be that the 2.02 version of the file that is built does not conform to the other .EFI files that are placed in /EFI/BOOT?