When I received it back in September I tried imaging it multiple times with multiple cards following the indicated instructions with win32 disk imager. All I got for my trouble was either scrolling text, black screen, hanging, or if I had the HDMI monitor plugged in corrupted color bands across the Linux boot screen where it effectively would hang during the boot process before actually starting Linux.
As RetrOrangePi talked about fixing the software side issues, I decided to put it to the side, and try again after they had a chance to address it. The current images are better in that I once after ~15 minutes did have the RetrOrangePi Full actually boot into EmuStation, froze after about 10 minutes, and refused to boot Linux in follow up attempts.
The current Supreme image is also better in that it doesn't have visual distortion bands when initially trying to boot Linux on the HDMI monitor. It fails to boot with multiple checks before it halts the boot process. I tried issuing the boot command to see if it would actually go through three times, and on the third time I got the distortion bands and a hard hang with a black screen on the actual handheld screen for my trouble...
The current error list is:
this is followed by multiple attempts with ethernet@1c30000 attempting PHY auto negotiation before the timeouts eventually fail. When I played with this recently it did it twice before hanging on the third time with distortion bands.MMC: no card present
Card did not respond to voltage select!
Device 0: device type unknown
... is now current device
** Bad device usb 0 **
** Bad device usb 0 **
missing environment variable: pxeuuid
missing environment variable: bootfile
I'm using a 32GB Sandisk Ultra A1 for the recent attempt, which is a different card from the previous attempts. I did notice when inspecting the card on my RPi 3B that Etcher setup the card so it has a single 4.81GB ext4 partition. I extended it with gparted, but that didn't change anything. At this point I feel like I should probably look at figuring out how to image it off the RPi because the way it's imaging the card is absurd.
I've not hardware modded it per video yet. Based on comments within that thread about black screen/scrolling text it sounded like you were indicating it needs to be swapped rather than hardware modded I thought it would be best to check in first.
I know I haven't went explicitly through the numbers, but I'm pretty sure I've addressed all of the parts that are relevant.