Comment 3 for bug 1749228

Please attach the logs from the installer once the installation finishes or crashes. It can be found in /var/log/syslog from the live session.

EFI or not probably should not matter here if the install fails in the first place; especially since you're installing from an SD card booted in legacy mode (so, not EFI, and whether EFI is enabled or not depends on how you answer the prompt to "force EFI installation").

I do remember seeing an issue with the partition number parsing before, so I'll look in up in past commits to see if we might have regressed there.