Unable to render MP4 HD

[shipdriver]

I have WMV 1080p30 source files that I am trying to render to an 5-6min MP4 HD file for upload to Youtube. I am able to make WMV HD files, but wanted to see if MP4 HD files would make a better final outcome on Youtube (Youtube seems to add a lot of jaggies to my WMV uploads). However, whenever I try to render anything to MP4 HD, VSX3 crashes (it never gets past the "Creating files" message). The windows error log states that the faulting modules are kernel32.dll and ntdll.dll. I have QT 7.6 (not the latest) installed. I have XSVX3 updated to SP2 (although the file downoaded was patch3.exe). In the Make Movie template and in Share/Custom , I don't get the option to see/manipulate any MP4 HD formats or even use H.264 compression. When I bring up Mpeg-4, it allows me to use mainly standard-def or non-HD resolutions and on-H.264 codecs. Is it not seeing the profiles/codecs for HD H.264 from Quicktime? Do I need QT Pro or just the free QT? I can render MP4 non-HD. As an aside, I see no sign that CUDA is being utilized.

[shipdriver]

I'm not sure how or why, but it started working and I can now share mpeg-4 hd. I'm as confused as ever because I didn't do anything, but I'm happier now.