I hope Tim doesnt mind, but while I was beta testing a bunch of newer versions of Opiereader, I recall Tim saying that he was/had put in chm support. You might want to drop him a line, or check out the newest \"unstable\" version of opiereader on his site (it\'s not really unstable, it\'s just newer). I havent talked to him in a while, I can only assume he\'s madly busy, but he might have some time to answer your question.
Yz