x64 Universal Install iso not working even after I remove ei.cfg

Hi All, I've been following the wonderful guides here on building a universal USB installer.
I've successfully made an x86 disc that install all versions fine, but my x64 iso is just limited to premium (the disc I got the original image from).

I've tried re-ripping the ISO, manually deleting ei.cfg, doing it with the utility to no avail.
Am I just doing something stupid? Why does the x86 one work, but not the x64?

Thanks,
Iota

(the disc I got the original image from).

Where did get the original image from?

I have a legit copy of x64 premium that i'm trying to make the universal installer from.

Run the ei.cfg removal tool on 64 bit ISO, Explore Sources folder to make sure it's gone, then write to flash stick using Universal USB Installer with Win7 in dropdown menu.

Alas, I used the ei.cfg utility, and created the ISO with the universal usb installer, but no dice. It just lists home premium x64. The 32 ISO works fine! WTH?

Okay, so I ripped the image up, manually removed ei.cfg and then used img burn to create an image file. That seems to have done the trick.

It appears the ei.cfg utility wasn't really removing ei.cfg. Very strange as it worked on the x86 iso just fine.

Thanks for the help gents!