This is the same behavior as the Platinum edition. If you have the console or the mutidoc floated and on the second monitor. It is now a separate window that has the same priority as a vst window.
What that means is that each window moves to the front as it gains the focus. So the full screen windows will cover any vst windows as soon as it receives the focus.
The main sonar window with track View however will stay behind the vst even if it has the focus.
I would suggest that you check out the feature request forum. I already submitted a feature request here.
http://forum.cakewalk.com/Change-how-xray-and-vsts-behave-Dual-monitor-wfloating-MultiDoc-m3209605.aspx pleas comment on that thread and rate the first post to help get more attention on this.