one of the bad things with getting a dog from many shelters is that they do get used to doing thier "business" in the same area as where they stay, which is likely the concrete of thier kennel. while only the most unhousebroken dogs in shelters go in the area where they sleep, they will get used to going in the outer part part of thier kennel. some of the best house broke dogs loose thier training while staying in a shelter situation. especially when they are younger they are easy to get used to going on solid floor over dirt or grass.
i know it seems like a lot of time, and it will take a lot of patientce, keep to what you are doing. it is sometimes hard for dogs on a lead to do the number "2". it leaves them in a vonurable(spl?) situation and most dogs when on a lead feel they have to protect not only themselves but also the person at the other end. which is why your dog is so reactive to everything going on around her.
if you no longer have the time for waiting for a "two", maybe look into getting an outside kennel of some sort, or even an invisible fence, so that you are able to let your pup out in an area that they will be safely contained while you walk away and wait for business to be done.
good luck and don't give up on your dogger! i promise, all dogs would rather do thier business outside than where they come into sleep!!
Trouble always seems to find me.
Then again, i've never been good at hide-n-seek.