I use the prayer list feature in Logos and since I upgraded to 6 it has been slow.
System is a Mac Book Pro Retina 15" Mid 2014 with 2.5GHz i7 w/ 16GB RAM OS X Yosemite 10.10.2
I have 30 items active in my list and 22 items in my answered list.
The problem is like this. The first few items that I click off seem to be ok, but as I go along the "beach ball" comes up and just does its thing for a few seconds continuing to get a bit longer with every click. In the end it can take 5->10 seconds to click off an item. During the time Logos is busy it is completely unresponsive.