I was able to successfully render the videos; first in Vegas as a WMV, then through Adobe Media Encoder to MP4 to get the 1:1 aspect ratio for Vimeo.
I'd love to understand what was going on. And understand codecs more appropriately as well, specifically how to manage them.
I made a list with InstalledCodec, anything look wrong with this?
http://secularuh.org/hosted/InstalledCodec_2012_07_12.htm