On a ASUS the only UEFI/BIOS firmware setting that needs to be reset is Secure Boot to DISABLED.
1) Downgrade to Windows 7.
http://www.eightforums.com/tutorials/13326-downgrade-windows-8-windows-7-a.html
Warning you must have the UEFI/BIOS firmware setting in Step Three set.
Make sure you read the
NOTE at Step three.
2)
If Using a USB Pen drive on a PC with a UEFI BIOS.
USB Pen drive need to be formatted to FAT32 as in
http://www.eightforums.com/tutorials/15458-uefi-bootable-usb-flash-drive-create-windows.html
Take
note of Step 11 for Windows 7.
Also you will need to use a USB 2.0 port, as there are no USB 3.0 drivers in Windows 7.
You will need to buy Windows 7.