You said you used an ISO, could it have been a standard x86 boot ISO, instead of one for MK-802 architecture? I don’t have one yet, but I’ve been thinking of getting one to play with. I’m subscribing to see how you do with it.
The author of that page said that he had to dink with his a bit… removing and re-inserting the micro SD card, power cycling the MK-802, etc. before it successfully booted into Ubuntu. Odd.
OK this should work. Run Puppy on another machine and then use the installer it has in it. There is an option for all sorts of media. Install it to what you want. Doing that will make that media bootable. If that doesn’t work then someone on this forum will be able to help.
BTW, I love Puppy and it is on, and bootable from, my EDC pendrive.
I’ve got an older laptop that won’t boot from an SD card bigger than 4GB. I would think that a current device wouldn’t have that problem, but who knows.
Your trials and tribulations remind me of putting Cyanogenmod firmware on my B&N Nook Color, trying to make a cheap tablet. I did finally beat it into submission, but it was a frustrating process.