I just purchased the MDS Automaton and downloaded MDS.
Tried experiment on MacMini with High Sierra installed.
After Booting into recovery and into the process, it pops this error:
startosinstall failed with return code255
Please verify that the recovery partition is not older than the macOS you are trying to install, and verify the certificate used to sign the install package is not expired.
I have verified that the recovery partition is set for High Sierra
I downloaded the installer from the MDS app.
What should I try next?