Trying to change boot screen graphic for my GB motherboard

The Internal

Limp Gawd
Nov 14, 2004
I've done this manually in the past, but was thinking about finding an easier way to change the boot screen on my Gigabyte Z170N-Gaming 5 mITX motherboard.

Gigabyte makes this program called "-at sign-Bios" which has a "Face wizard" that's supposed to do just that (change the boot graphic).

However, whenever I run it, it looks like everything is doing fine, then "Warning: Logo file or BIOS image is write-protected."... and no change. The documentation for the program is non-exsistant. I don't know if there's a max or min resolution or a specific file type.

I've tried .jpg and .bmp files thus far, but no go. Anyone know anything about it or have Windows 10 friendly alternatives?
How the heck do I un-write protect the BIOS image file, anywho?