Hmmm... I have not tested much with Vista64 myself, however I do know of a small handful of users, two of which are big time users of the software, and have tested the batch download function. So, I'm not sure. You said on a 'home computer', is the Vista64 computer somewhere else with a different connection?
I do wonder about the box not showing up -- a graphics glitch like that suggests a video card issue. Updating drivers is the usual prescription.
The next beta (out very soon hopefully!) has the color (and WMS server tilesets) split out by resolution so you can do 0.015 only, or avoid 0.003 or whatever. You may want to wait a bit and use that.