Short-sales can be frustrating and time consuming. When dealing with a short-sale, you should use a Realtor who is a short-sale specialist.
I do quite a few property valuations and it is common to get an order for an interior inspection on a short-sale a few days before it is scheduled to close. I have seen deals fall apart because there has been a substantial change in the market conditions.
I do know that every lender is different and the only thing that is certain is that short-sales are not short. Good luck with the transaction. Again, you should look for a certified short-sale specialist.