I've noticed that if I try to connect to the VM Host Server via an RDP session within another RDP session then when I launch the VM console and look at the VM desktops I get only black/blank screens. I think this is because the embedded RDP session is limited to only 8 colors whilst the VM desktop is in a glorious 16 bit colors and so cant be viewed at the lesser screen quality.
I didnt foresee this one so working from home last week was painful!
I thought this might interest someone.