I too went down the rabbit-hole intending to get a dual boot Windows 8/Linuxmint 14.1 install on my new G580 with Phoenix SecureCore Tiano UEFI BIOS (version 62CN90WW). In my case, I started by writing a Windows 8 64bit Repair Disk DVD and a 16Gb USB stick recovery disk image from the Lenovo tools, and then downloaded the Linuxmint 14.1 Cinnamon ISO and wrote it to a DVD as well, all under Win8.
Trying to boot from either Win8 Repair or Linuxmint 14.1 install proved problematic: I could never get either DVD to show in the Boot Menu at that point. I then tried the unetbootin approach and had it use the Linuxmint 14.1 install ISO image to make another 16Gb USB stick. I set the UEFI BIOS to allow USB booting, and booted off the stick; however, like you I only got to the text menu: selecting anything only either got me to a black screen or the grub menu.
Then I found a setting that made both the Linuxmint Install stick and bootable optical media show up: in the UEFI BIOS, I set the boot mode to allow Legacy Support (though still with UEFI First). Lo and behold, the bootable optical media started showing up in the UEFI Boot Menu; I only booted off the stick though since it was faster (and less noisy) except for a proof-of-success with both the Win8 Repair and Linuxmint Install DVD. With that one setting change though, both the DVD boot and black screen problems went away: Linuxmint now boots normally to the desktop for install etc.
I did notice one further odd thing though: when I reset the UEFI BIOS to its "Setup Defaults" later on, the DVDs still appeared in the Boot Menu even after Boot Mode went back to UEFI. At that point, the Linuxmint boots went back to the black screen/grub only prompt problem until I set the Boot Mode back to Legacy Support again.
Hope that helps...
My sad tale of trying to install wubi-style on my Win8 partition and how Boot-Repair broke my Windows 8 boot without ever coming close to a Linux boot is for another post. The breakage turned out to be Boot-Repair and my ensuing repair attempts setting Boot flag on two GPT partitions and something erasing the EFI BCD database entry for Win8. Between gparted on the Linuxmint install DVD/stick and diskpart/bootrec/bcdedit on the Win8 Repair DVD, I eventually unsnarled the mess and undid/overwrote most of the wubi-style install/Boot-Repair/auto repair I did to myself.
Now I am back to semi-scratch (though my Secure Boot status seems semi-permanently disabled, and my UEFI BIOS Boot Menu now has a "Windows Boot Manager" entry in it as well as the ATA HDD that used to be there; at least the ATAPI CD DVD-RW is there as well