A general cooking tip--the first time you try something, be it a recipe or a box mix--follow the directions exactly. If it doesn't come out to your liking, you know the problem isn't you. The second time you try something, you can alter it if you like (or, in this case, try a different brand).
Something like that, no problem. I was talking more things like refrigerating the dough or adding additional leavening.
It was the and/or yeast that's kind of puzzling to me. Yeast only helps to rise with time. Baking powder or baking soda will rise with high heat. Not sure why they would need yeast unless it's because it gives it a yeast taste.