Go back and rerun it without the "%" sign in the desired static margin.  That should fill in the NaN nonsense with numbers you can use.  The final location for your balance point will be the number it gives you for the distance back from the LE at the root.  that's where it's easiest to measure.

The 44.6% point is the Neutral Point.  It's the furthest back you can put the balance point and still fly without the model trying to flip around and fly backwards.  Contrary to what it says on the notes about setting the value for the static margin 3D models are often set up with SM's between +5 and -2'ish to achieve the ability they have to flip around.  But it increases the work load on the pilot to keep the model under control. 

You may eventually end up at that point but for now your 10% value for stability margin is a good beginning.  But depending on how you like to fly it won't be your final point.  I would suggest running the numbers again for an SM of 3 as a guide for the rearward limit so you know what sort of tolerance you have for later and can work your way back in small steps until you're totally happy with how the model flies and it's not too much workload to keep it under total control.