sure wish I could help you naomi...I am in the same delimma as well, my little molly is preg and about to deliver her fry. I have just as many questions as you do. I am pretty sure you will need to keep the baby away from all the adult fish until they can't fit into any of the adult's mouths...(apparently they will eat their own, ironic) you should put the baby in a breeder net or box and feed it very small amounts of fish food, (crumble up the food you have and feed it about 3 times /day) she will prob have more babies so keep an eye out, there might be some hiding out in plants if you have any...like I said, watch out for the other fish, they do eat the babies
keep up the good work and congrats, can't wait until my little one has her own little ones as well!