"1) It looks like the air filter in my car but it also looks like an enormous heat sink."
Yup.
"2) Where is the three inches of lead shielding?
"According to Rossi"...the ultimate "core" (in which resides the nickel nanopowder) is 20 cm by 20 cm by 2cm. The lead shielding consists of 2cm on all "faces", and the heat exchanger is "on top" of all that.
"3) Rossi isn’t churning these out in his garage, someone had to make over a hundred of the cases and lids for the fat cat and it’s not a trivial task unless he’s stamping them out like an oil pan."
This has been one of my major points ever since the 1MW system pictures showed up. A "hugh" amount of work is being done "somewhere" to put all this stuff together.
"4) It doesn’t look like it could hold a lot of water if we assume the heat sink center block is solid."
See #1. There's probably quite a bit of volume between those heat-sink fins, which are on both top AND bottom of the "core".
"5) The lid needs a lip like on an oil pan or it will expand between bolts."
I hadn't noticed this detail.
"6) It looks like he’s using gasket sealer instead of a gasket, bad idea in the long run but this is just a prototype."
Which prototype is probably assembled/disassembled multiple times. I think this is an argument "against" using a gasket sealer (or at least one that "sets up" like silicones do). He may be using a "grease" type that doesn't "cure" after assembly just for that reason.
Do you think there is enough room in there to hold 8 gallons?