The biggest difference between a hand pie and a turnover is the dough that the filling is encased in. Hand pies are usually made with pie dough, while turnovers are traditionally made with puff pastry.
Instant yeast is bullet-proof and will rise on anything. The three yeasts that need activation are active, baker's, and starters. If they are not properly activated, then they won't rise properly.
Substituting sugar with liquid sweeteners can seriously throw off the ratio, and these ingredients vary drastically in weight and volume, so they can't be substituted 1:1.