Strange. Following a recent crash and reinstall, my V12 build 536 also had no QT templates - I checked after replying to you. Now I have just downloaded and installed QT 7.7 and Quicktime now appears in my render options.
I don't know what K-Lite is... I haven't installed any other software other than a few vsti's. I made sure to disable all of them in Vegas. I didn't have a vegas job for a couple of months and noticed as soon as I "upgraded" to 536 that I was unable to render out to my DNxHD codec. I posted something about that last month but got no real response. I just finished a vegas project. I did a clean install of both VP12 , Avid LE 2.3.8, Quicktime 7.6 and I said a few cuss words...just in case.
Still no luck.