So I was curious... I can read the Da Vinci's SD card files, but any time I try and save to the sd card, it hangs on uploaded. Anyone had success fur this for an "untethered" print?

I was never able to get it to work on Windows and I dont think it does. I just removed the card, I use and extension cable that puts the card in the ptint area. Once removed I plugged it into my laptop's card reader and put the gcode on that way. Then put it back in the printer, booted it, and printed the file from the LCD. Rep host/firmware has/had a bug with its comm protocols that will bite you later it will lock up and no longer allow the temp to be controlled so it can runaway and reach dangerous levels. Newest version may have fixed this. It will also loose comm during a live print and cause the print head to just stop in mid print melting a hole where it stops.

The firmware is not talking correctly to the printer. It is not waiting for the printer to acknowledge it has recieved data. Instead it just streams the data to the printer until it is done and the printer will only print whatever manged to get in the buffer. The rest is just lost. I think the same issue is what causes the host to lock up and allow the bed and hot end heaters to run away.

With mac and linux you can play with the python program, after getting the pyserial module.
Get the usb device  name from the /dev folder when you have plugged the davinci into your usb slot.