S. Krezel - Smart Spline Generator

hello i recently purchased this powerful tool…but i cant figure out how it works lol i am using it to place ivy from a palace to another one but looks like the spline blueprint is not working as other spline generator… I can’t drag the white square from pivot to add more mesh at spline like usually spline generator do… i need to place the spline from a point A to B anybody can help me? thx