Insider sells are permitted by the BoD, as they see fit. These would not be deemed determental to on-going negotiations with interested parties since their interest is not share price oriented, but product oriented.
Insider buys, on the other hand, tells the whole world that management wants more of the pie, raising awareness of the stock when the company wants less awareness due to NDA's. Why force yourself to be asked questions that you can't answer?
Furthermore, the regulatory issue does not go away; you should take it as a positive sign that insiders aren't allowed to buy.
Not sure what you are referring to about reading too much into NR's...to me, this is simple logic.