It appears I should have used Clonezilla to backup instead of the snapshot ISO tool.
Upon install of custom ISO, chose to install GRUB to MBR, which likely led to Boot Fail. GRUB rescue prompt is all I see, now. I dislike GRUB2 and just as soon not have to deal with it. A SuperGRUB2 10MB iso download failed to boot, also, after burning with Pburn on Slacko -- how I'm writing this.
What good is a snapshot if it messes up the bootloader, or did I do it by reinstalling it?

Possibly something went wrong during install however that doesn't explain why the supergrub2 disk didn't boot (mbr boot loader is.not used in a live boot).

I assume the custom snapshot iso boots ok?

Just installed antiX-16 Base and went from there.
Haven't had much luck with MX last two times I tried to install it.

And no, dolphin_oracle, the ISO would not boot. I am beginning to suspect the old samsung EVO ssd is showing its age, but could be wrong. Changed it out, too.

Thanks to all. I'll just keep plugging away . . .