The calculations are actually still done the same.
Preflop is easier to build an interface around, which is why I chose to focus on it for the first iteration. PokerStove's postflop range selection tool worked, but I felt it could have been done a lot better. For example, how would you select the range "A2s-ATs of hearts and clubs" using PokerStove? Making a clean way to select that would have been the next step for ALL IN Expert.
Preflop is easier to build an interface around, which is why I chose to focus on it for the first iteration. PokerStove's postflop range selection tool worked, but I felt it could have been done a lot better. For example, how would you select the range "A2s-ATs of hearts and clubs" using PokerStove? Making a clean way to select that would have been the next step for ALL IN Expert.