This is probably unrelated to the multiple texture sets setting in that case. A couple of reasons why one group would not affect another: * Ignore Groups is was disabled in the AO settings * Exclude While Ignoring Groups was enabled in the Low object for one or more groups. This setting will prevent AO from casting…
When baking AO using multiple texture sets, objects that are using one texture set aren't affecting AO on objects using another texture sets as if "Ignore groups" were unchecked. I created a simple scene to demonstrate the bug. 1. First object using texture set #1 2. Second object using texture set #2 As you can see AO…