If I have a Huffyuv file that I eventually want to burn to Blu-Ray with DVD Architect Studio, do I even need to convert it to .m2t or whatever first? Won't DVDAS make the necessary compression at whatever bitrate I select?
The closer the file you load to DVD Architect is to the final BluRay output, the better your results will be and the faster the program will work (with less likelihood of choking in the process).
I very much recommend you create a BluRay ready file with Vegas and port that over to DVD Architect rather than use raw footage or footage that uses codecs that require a major transcoding.
You will not get optimal compression or quality by rendering in DVD Architect.
Do it in Vegas to an optimized BluRay template.
Letting DVD Architect do the rendering is for soccer moms.