Good morning John and welcome to the forum. I am a mother of 8, so bless you heart for wanting to make something special for your family. I hope they appreciate your time and effort.
I haven't tried a cheese using powdered milk, but I know that there are some excellent brie cheeses that are made on half raw and half powdered milk, so as long as you get the milk to a setting curd, I would presume that it should work fine.
Aging is to develop the flavours in the cheese, and the longer you allow to mature the stronger the flavour. So you can, if you want to eat immediately, only you have to accept that if may not have much flavour. The universal problem most of us have is letting the cheese mature long enough before we just have to open them and try them.
Just noticing you screen name and the car pic. Was wondering if that was low level flying you are doing?
Anyway keep us informed on how the cheeses are doing.