You can just skip to the last paragraph for a summary of what to input, but I thought I would explain the reasons behind the number.
You've given an ideal set of numbers to reference the sugar contribution. Plato is a weight percentage number where 1 Plato = 1 gm sugar in 100 gm solution = 1% sugar by weight.
You want to reference it as a per pint addition and a pint of water weighs 16 oz or 454 gm. So, 216 gm of sugar in 454 gm of solution is 47.6% or 47.6 brix. This is a specific gravity of 1.2196 (1.220 rounded).
Using that gravity as a weight and telling BeerSmith that it is 1.220 as an extract or sugar won't work. All gravity contrubutions are based on gallon (or liter) quantities. So, you have to consider what that juice will contribute per gallon.
A gallon of water weighs 3780 gm. So, simply divide your reference of 216 gm sugar into a gallon and you have a Plato contribution of 5.7. Converted to Specific Gravity = 1.023 per gallon for each pound of extract added.
Enter it in BeerSmith with grains. Add it to recipes in pounds (a pint is a pound). Set it as extract, with a potential of 1.023 as this is the per gallon gravity. Personally, I would add it "after the boil," directly into the primary. There is pectin in fruit that can set a permanent haze if heated too much. The manufacture of concentrates makes them aseptic, so no contamination issues can arise.
