I got a C6 to be mined but the C7 was lost because spynode got into trouble with block hashes again.
I had totally restarted with empty spynode folders and cold boot of my machine.
So nothing wrong on my operations as far as I know.
There is definitely a huge problem with the daemon on certain blocks.
I had worked around it previously by creating a new wallet address and funding again so that the
wallet was in a block beyond where spynode choked, and I set the start hash there, beyond where the
problem block was. That got me running OK again for a few more weeks until yesterday.
But now again it is choking on some recent blocks.
I am attaching the daemon and client logs.