CG location hasn't been a problem since about the time of the Wright brothers. Honestly.

It's not a hard problem at all for most of our planforms. The aero industry worked out a fairly simple formula (as aerodynamic formulas go) that works great and any idiot can easily use. All you need is a yardstick or the numbers off the model plans.

Measure your root chords, tip chords, spans, LE sweeps, and tail moment. Plug those 9 simple to do measurements into the formula, add the Static Margin and (on the internet) click COMPUTE (or whatever the app button is labeled).

If you run the numbers through an application like you find @ http://www.geistware.com/rcmodeling/cg_super_calc.htm, you'll get a reliably safe CG range if you use something like 5% and 15% Static Margins.

You're actually looking for a safe starting CG, and that's really simple.