No way to leave UEFI/EFI unchecked?
Why I ask is that I like that the Clover EFI partition is hidden after a clean OS X install and I can manually make it visible if I need to update something in there. When installing scripts I also have to reinstall bootloader and reinstalling it makes EFI partition visible again. Also reinstalling boot loader installs all the 32-bit stuff back which I have deleted
You may try this tools