Bill, downthrust is there to compensate for the small decalage. Even though both wing and stab are set to 0 degrees incidence angle, the zero-lift angle for the 2419 wing airfoil is about -0.6 degrees. If you set the wing to this incidence angle you should (or may) set downthrust to zero. (I checked that in a simulator.)

Right thrust is another cup of tea. Since it should make up for the effects of prop torque, which are quite noticeable with a 12x6 prop, you may leave it as is. There's virtually no drawback if nearly all maneuvers in the schedule are positive-g. But right thrust is a matter of taste.

My 2 Eurocent...