This is more fully described here: http://forum.joomla.org/viewtopic.php?f=710&t=799086

The problem goes away if the Hathor template is selected - so there must be a bug in the ISIS template itself. I thought it might be fixed for 3.1, but the problem is still there.

In essence, when the plugin is selected it should show 4 tabs of parameters. Whilst the 4 tabs are there, clicking on the tab name (i.e. to select different parameters) does nothing and just continues to show all the parameters from the 1st tab.