rMBP 15", 1920 x 1200 native, Coherence, Windows 10 1920 x 1200 problems

Hi,
Running El Capitan with Latest Parallels and Windows 10 updated. I am running 1920 x 1200 Mac resolution but I am unable to get Windows 10 to the same 1920 x 1200 resolution. I am trying to run in Coherence Mode.

1. Fresh from blank disk El Capitan install. Installed Parallels and Windows 10.
2. VM is running in Scaled and not Retina resolution as recommended.
3. In Windows, character sizes set to 100% as recommended.

Attempts to change resolution to 1920 x 1200 do not work. The screen resolution changes to another setting and Windows 10 exits Coherence View mode.

TIA for advice.