I had to stop the pool as at 8:00 findblock routine still find block height 471794 forever (it was an already find blocks).
Most of the case this is due to fork, the other to findblock (it need to delete that blocks to recover, but in this case it not help).
For recover I have to change the server wallet with a new one and move money from old to new and for this I need a secure computer, so I can do that operation only this night.
So, I start to download the blockchain from scratch, to be sure that if this was due to a fork, it fixes the problem.
Sorry for the trouble, but with this low difficulty an involontaire fork can happen.
Exactly the same thing happened to me today. I've been mining a little on my private server and findblock got screwed up somehow, kept finding the same block 471757.
Not sure if it was a fork, looks like server blockchain was at correct blockheight.
Re-downloaded blockchain and started with clean new wallet, everything went back to normal.
We need an updated wallet asap and then a new good looking RE-ANN topic.
Then we will be able to push GRW to some major exchange and get GRW really growing.