This is a problem I'm having with Architect 6.0, Build 237, I moved the whole project to the latest version from Magix (can't find any build number), and I got the same crash. I even completely rebuilt the whole thing just in case my original DAR was corrupt. Same crash. I have a 17Gb project going to BR. Did all the Blu-ray construction, saved to a DAR file. Did the "prepare" function, which is to create the ISO files for the final burn. I hit "render" and about 2/3 of the way through the render I get this:

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An error occured while preparing compliation

File name: 00001.m2ts
Status: mscorlib.dll::ThreadHelper::ThreadStart_Context::Video buffer underflows. -

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The project played just fine in preview mode. I'm using all the same settings I've used forever. I rendered a AVC file in Vegas 14, and dragged it over along with the AC-3 audio.