I set EnableSelection="False" EnableHotTracking="False" EnableExpandButtons="false" because I wanted to use it as a set of collapsible panels but even with the EnableSelection set to false it still allows selection of the items in the groups which of course changes all of the CSS in the selected item. Have I missed a setting somewhere? I even tried cancelling the ClientEvents-ItemSelecting event to no avail.
I overrode the CSS classes that change the background image and that solved my problem. I would have expected that disabling selection would also disable Activation as well.