Should be fixed now.
It was a simple issue of a broken symlink in the python-support package. I at first made a kludge in the python-cairo startup script to enable cairo to be imported, but then virtinst could not be imported. I saw there were broken symlinks in the python-support package. /usr/lib/python2.7/dist-packages/python-support.pth and /usr/lib/python2.6/dist-packages/python-support.pth. Those are the files that set the python path so it finds modules, very important and surely affects other python related packages as well.
Some files in Debian packages are relative symlinks, and that works as is when installing those files to the filesystem, but do not work when symlinking them. The fix is to simply copy those symlinks to the live filesystem, so the relative path thing works. "rm /usr/lib/python2.7/dist-packages/python-support.pth && cp -a /tmp/tcloop/PKGNAME/usr/lib/python2.7/dist-packages/python-support.pth /usr/lib/python2.7/dist-packages/" takes care of it in the startup script.
Broken symlinks in any package is always a red flag. Using the below command identifies which files in the live filesystem are broken symlinks, install the findutils package for this:
find /usr -type l -xtype l
I detail this so that advanced users can help in testing and finding issues as they arise.