Default [Q] From Cyanogenmod 11 to 4.3 HTC RUU

As the title suggests, has anybody successfully installed the 4.3 HTC RUU while running Cyanogenmod 11? I've been out of the flashing loop for a while and am quite rusty. I tried running the RUU.exe and the phone connects via fastbootusb just fine. It ran for about an hour before I gave up. Stuck at the sending................ screen.

I guess what I need to know is do I need to be back on stock ROM for the RUU to work? If so, is there any danger in flashing the stock ROM now that I'm running CM11 with the different partition scheme?

Another question. Do I need to oem lock my device before installing the RUU. If so, how is that done?

I am unlocked, S-off courtesy of moonshine, HBOOT 2.09.4444, RADIO
HTC EVO 4G LTE cm11 nightlies
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