I have a website which describes one way to handle condensation. I have completely enclosed the peltier/waterblock/CPU in 5/8" layers of insulation, sealed with beads of silicone, and enclosed in a Radio Shack 'Project Box'. It works well and condensation is zero at -55F. The site is
http://learn.to/christekcool/
Hope this is of some help. Good luck.
Chris @ chrismb1@juno.com