Comment 2 for bug 1172993

You can see the problem in the end of DpkgTerminalLog.gz :

usermod: user 'root,brandonallenpdx' does not exist
dpkg: error processing kismet (--configure):
 subprocess installed post-installation script returned error exit status 6

You need to specify the user in a "space-separated" list, not a comma separated one.
Could you please purge the package:
  sudo apt-get purge kismet

and then install it again?