We were having trouble with poos in the potty too, got our first one last night , but yet to see if it will keep going.
Over a period of 3 weeks everytime DS did a poo in his nappy or knickers we would say big boys don't do poos in their nappy/knickers they do poos in the toilet or where do poos go DS? - that's right in the toilet and get him to take the poos to the toilet and flush it.
He then asked for a particular toy and instead of just getting it as his once a week buy we told him that he could only have it if he did a poo in the potty - placed the toy in a clear sealed container so he could see it and everytime he said I want "xxx toy" we just repeated when you do a poo in the potty.
The no-cry solution suggests wrapping little prizes and giving them for successes.
Take them to the potty first thing in the morning and after meals.
If he asks for a nappy to poo in, make him do it where the potty/toilet is; progress to him sitting on the potty with the nappy on, once he is used to that suggest taking the nappy off and line the potty with the nappy or cut a hole in the nappy.
Good Luck.