I have found adding new cards to 861 to be pretty intuitive. Just go into mconfig and add the new card (along with the connections that will be made in the drag-n-drop menu) by clicking on 861 in the system diagram. The program will show you where to put the card in the chassis - although this is not anabsolute requirement as I know when I tried to add the IA45 mch card it instructed me to put it into a slot that was blocked by an internal half card. So I ended up putting it into a different slot and it works fine.

My Kit: 861v8+ID41, 800v4, UHD722, MD600, MS600, MS200, Oppo BDP-203, Genesis 201, Genesis 350 SE, Genesis S4-8 Sub, BG 520i, VTL MB450 II, Krell Showcase 7, Genesis 928 Subs, Danley DTS10 sub, SVS Ultra 16 subs.