Sounds peculiar. If they sent YOU a counter offer and you accepted the counter offer then the only remaining item that is needed is confirmation of the counter offer you signed. Did escrow indeed open? Have you started your loan processing yet? Did you send the accepted counter offer along with the original purchase agreement to your loan officer? Do you have an escrow number?
As Viz posted, most REO transactions will indeed levy a fine upon the buyer on a daily basis if the escrow does not close due to the buyers performance.
What is your realtor doing to help you out? My advice is that you get an addendum generated immediately stating that escrow will close 30 days from the day that you received a confirmation of acceptance from your accepted counter offer.
If you have indeed signed the addendum which is generally the liability release then no there is not much more that you will get. The lender may send you some token disclosure information. I assume you will also get a CLUE report and an NHD, (Hopefully your realtor asked for one) along with the cookie cutter local area disclosure. You should also get a termite inspection report. Even with REO properties you should get one (again assuming you asked) and that pretty much wraps it up. Then all the other work is your due diligence.