PoW ran during the ICO and lasted a couple days. Suprnova was the only pool on at launch. I cannot access their block statistics to see what block they get in on now, I'm sure ocminer can tell us when he sees this. A few solo miners also got in at launch, I do not know how many blocks they got. Development team have the first 4 blocks from getting the ICO funds. It kicked over 4 total blocks before the gpu was shut down.

As to the destroyed 36,491,965.0 coins residing here https://chainz.cryptoid.info/maryj/address.dws?3964.htm

Pride generated a mammothcoin address, and then sent those 36,491,965.0 to the mammothcoin address. He then destroyed the wallet.dat of the wallet sent from. They do seem to still be showing in the blockchain. C-Cex has guaranteed us that they are no longer accessible. We are looking into the matter and will let you know as soon as we know.