Ron, you will be fine as it is. If you shim the tailplane leading edge down you will increase the 'longitudinal dihedral', decrease the 'S&L' cruise speed, (cause the tailplane will try to maintain the main wing at a higher AOA) and slightly change the fuselages flight attitude. The old speed trim thing again. Leave as is, balance at 25% MAC for the first flights, and see what it is like. Then try playing around with the rig. Yes, the various rigging angles are DEFINED by the relation of the CHORD LINES to each other and whatever DATUM the designer has chosen. (And that datum can be any line, anywhere, it is only a reference). The CHORD line is defined as that line that joins the centre of the Leading edge radius and the centre of the trailing edge. And we try not to have 'semi-symmetric ' wing sections, that's a bit like being just a bit pregnant, something is either symmetric, or it is not. Better to define your sections by describing the CAMBER, that line half way between the top and bottom of the wing section, ie the line that divides the wing section into equal areas, top and bottom. In your case you have a wing section with a bit of positive camber, which is usually expressed as a percentage of the wing chord (there's that term again). A symmetric wing has, of course zero camber, or you could say that the chord line and the camber line are the same.
Evan, WB #12.