Understanding my current system

I know some of this is very elementary to many of you. I have attached a diagram of my current oil fired system with proposed water storage on the right and BoilerMate indirect DHW to replace the "in furnace" water heater (hate it) on the left side of the furnace.

Can any of you show me where to pipe in the outside wood gasifier to this exsisting system so the oil boiler remains active in the event the wood fire should go out?

Maybe someone can take the jpeg and add to it. Im trying to understand how a system like this will work so I can forge ahead with some real work.

One possibility would be to plumb it in parallel with the oil boiler - give it a pair of circ pumps just like the oil. Might take some head scratching and a couple of relays to get the control logic figured out, but it would make the two systems independent.

I did a similar approach with mine, except that I have one circ for each boiler and zone valves to control which zones get heat. If you haven't checked it out, I have a schematic on my site.