Would this adapt to being done in a crockpot? I'm thinking leave everything up to step 4 then stick in crockpot on low for 7+ hours?

I love this recipe -- I make it every winter. Agree with nutcakes that this recipe should work fine in a crockpot. However, slow cookers tend to retain a lot more liquid than other cooking methods, so I would only add enough chicken stock/water to barely cover the ribs. After the ribs are finished cooking, you may want to further reduce the sauce on the stove top to thicken it before you puree it.

I think that would work out, no problem.