Regarding the full flying stab-
I've been looking into this for greater authority in 3D manuvers. The mechanics are pretty simple:
1. Put the pivot point ahead of the MAC so that ther is always a positive load on you servo. To avoid "snatch" as the stab rotates.
2. Use a carbon or aluminum tube as your spar, nylon, delrin or another tube as the bushing surface.
3. Control the surface via a pull-pull wheel or elongated horn mounted inboard of the surface between it and the fuse.
In use a full flying stab is very tricky, you either use it when the stab size makes it less effective (Fokker Dr-1 rudder) or you use very small throws. My attempts at a full flying stab with +/- 45 deg. of throw resulted in a plane that was prone to pilot induced occilation. Some slope soarers and the Diabolitin have aerobatic flying stabs but I thing that the long tail moment allows them to be more controllable.
Basically, unless you are copying an exhisting design you'll just have to try it out.
The fixed stab would not be controllable if you lost the flying stab. You would still not have pitch control. With flaperons you might be able to coax the plane down.

Chris