A nice feature inside the Markup manager I use daily is the "View DWF Geometry". This little button can be really helpful when working on a DWG file that has tremendously changed since the DWF was marked up. This button will actually make all DWG geometry invisible and show the vector lines from the DWF right in the same location that the DWF was plotted from. There is also a couple other buttons. I use the "View DWG Geometry" to turn off the DWF lines and turn back on your DWG lines. And sometimes use the "View Red line Geometry" to toggle the markups on and off. There is sometimes where the Red lines get too confusing and need to be tamed down a bit to work and make revisions.
Now there is ONE BIG problem with this "View DWF Geometry". In order to view the DWF geometry, you HAVE to have a background color other than black. I would recommend something other than a dark color. Mainly because the DWF Vector lines will show the same color they are in the DWF. So if you have black on black you wont see anything. I would recommend a white background, but we all know this white background can be a little hard on the eyes. So give a couple other colors a try.