Excellent, thanks for the clarification, much appreciated!
Yeah, the Bubonis one is a wee bit confusing, i think it's safe to assume from the way it was originally modelled, and the cost that he has 2 plague cannon (i think the plural of cannons being cannon doesn't help!)
The original Citadel Journal article would seem to support this >
http://nurgle.stelio.net/char_Bubonis.phpThe only contradiction in the NetEpic Chaos book would be that he also seems to have a power fist, and it is present on the hit template when the 2nd cannon should be.
Ach well, i think if I do ever run him i'll need to get some agreement from my opponent first.
Cheers,