Sure - I've attached two files, PM 5 & PM 6. PM 5 is from my Windows 7 copy of PhotoMechanic, V5 and this is what I'm trying to achieve. You can see that Favorites is stacked above Navigator.
PM 6 is from my Windows 10 copy of PhotoMechanic V6. This picture shows the best I can do with these in V6, i.e. they are adjacent. If I make either floating it winds up all over my screens and sometimes becomes invisible. I've tried dragging & dropping & going back & forth between dock & float. I'd like to have them stacked so that the contact sheet window is as large as possible.