Help flashing BIOS for z170- A

Hi, i want to flash a modded bios on my Asus Z170-A, followin this guide: [Tool Guide] AMI Setup - IFR Extractor AMISetupWriter But i dont know how to make a EFI-bootable drive, i tried Rufus but i cant make one unless its using a windows ISO? I also deleted the keys for my secure boot, but when i reboot they are back? What can i do?

@friskies - Flash it from windows using FPTw, or DOS with DOS FPT I assume that’s what you were using, FPT backup that you modified? If you are not using FPT dumped BIOS region that you modified, do not flash with FPT (ie do not flash stock BIOS you modified from Asus)
Here is guide - [GUIDE] Grub Fix Intel FPT Error 280 or 368 - BIOS Lock Asus/Other Mod BIOS Flash

Thanks, i used that guide to remove the BIOS lock. I backed up the current BIOS with FPTW, but UBU now hangs when updating the microcode on the backup: [Discussion] UBU Tool related Questions, Reports and Suggestions (43)