Was able to flashback to 1303 after clearing CMOS then upgraded back to 1715.  Going to stay there for now until they fix the 18xx series BIOS versions.

My guess is it is set behind the scenes like it was with previous BIOS versions. You should be fine. No issues with EXPO being enabled for me.

They are not available to set according to the settings files.

Do you know how to do it successfully?  I've tried BIOS Flashback but it never works.  Tried going back to 1715 myself as I had better performance overall with it.  Tried both FAT and FAT32 (and this isn't my first time doing this, it just doesn't se...

That is very odd.  Usually it's press F1 or F2 to enter BIOS setup (I can't remember) when it clears the CMOS.  Did you try using the clear CMOS button, which I believe is next to the BIOS Flashback button?  You could also try another keyboard and us...