Netios 0.72 fixes some bugs with the show_run mode and large config files. I also found some issues concerning the prompt detection, so it should be fixed now.
Complete changelog :
2010-01-14 (0.72) Jean-Christophe Baptiste <email@example.com>
* ciscoclass.py : forgot to remove a debug print
* ciscoclass.py : finish and fix a bunch of bugs in the show run function, format the config file properly
* ciscoclass.py : fix the prompt regex
Check there (tools page) for more details and a download link.