I was wrong, DMute
http://dmweb.free.fr/?q=node/698 should be able to open and save your CSB saved game. Note that a bug will corrupt the champion portraits but apart from this it should work fine if you want to boost champion skills and statistics.
If someone wants to tinker with saved game files, here is the documentation I have so far (as well as a script to decode saved game files):
http://dmweb.free.fr/?q=node/1389