I don't know if you can call this a bug per say, I find the Corona VFB acts strange when you render using render nodes managed by BackBurner (don't know if it does the same using other managers).
When a render node receives the job and begin to calculate, the VFB window is extremely small and the view scale is set to 1:32 !?
When you resize the window dragging the frames, and zoom in to a better scale the window tends to stop updating.
I don't know if the use of Windows Remote Desktop have any influence on this - this is the way I keep an eye on the various rendernodes in my render farm. I haven't had any possibility to check this behavior without WRD, as my render farm is placed on another floor in my office.