Dual boot of two Windows 8 instances in EFI PC failing


I purchased a new EFI PC with Windows 8 preinstalled. I partitioned the single hard drive to house a new partition for Data and a new partition for another Spare OS. I copied the original Windows 8 partition to the new empty partition to use as a dual bootable spare OS copy in an emergency. I used EASYBCD to setup the dual boot environment. I used the "add new entry" feature to add the second Windows 8 partition to the boot menu. Everything looked OK at first. When I booted the original Windows 8 it worked fine, however, when I tried booting into the second Windows 8 it was unsuccessful. I just got a black screen immediately after selecting it. Upon examination of the EASYBCD "View settings" display I noticed the following discrepancy. The working (original) instance of Windows 8 has a Bootloader Path of "\Windows\system32\winload.efi". The non-booting instance of Windows 8 had a Bootloader Path of "\Windows\system32\winload.exe".

Intuitively, since it is an EFI machine, it appears that the non-working instance should also have a path to winload.efi not winload.exe. Why is this happening? Do I have to somehow edit the Bootload path to indicate winload.efi? Is there an EASYBCD or Windows 8 EFI limitation I am violating?