For now, I would stay away from UEFI : UEFI alone is already a serious pain in the ass, added to PXE boot, it becomes a nightmare.
I dont even want to imagine what it does when adding Android + PXE Boot + UEFI : Sounds like headaches too me
I have never been successful in dual-booting a laptop with Windows 8.x and Ubuntu x.y in UEFI mode, no matter what I fiddled with, e.g. Secure Boot etc. Always I was forced to switch back to Legacy Mode, with out EFI partition and GUID partition table and write an MBR.