Resolution Problem with two screens

Hey,

after installing PD9 and using a bootcamp 8.1 as VM I'm experiencing heavy resolution problems with working on 2 Screens.

Either i activate the "retina support" and the Sizes are ok on my second screen, but the sizes are way to small on my retina screen
or I don't activate it and the sizes on my second screen are way to large, but they fit the retina well.

how do i have to adjust it so that looks fine on both screens?

thx
Patrick