Were do you get Macadmaina butter? That sounds pretty good. All the same, I think the process in the OP is way to complicated. This could hardly even be considered cooking, let alone rocket science.
I get the mac. butter at a local food co-op. I bet you could get it at an Earth Fare or Wholefoods equivalent.
I keep on working on this recipe. I am trying to get most powerful and efficient firecrackers.

I can prepare the butter and sandwiches while the oven preheats.
I posted the new incarnation of firecrackers on the what to do with 5 grams of bud thread.
Preheat the oven to 330 f
I grind in a coffee grinder. Add powdered cannabis to to natural peanut butter. I run the grinder with a small amount of vegetable oil to collect all of the trichomes left in the grinder. Poor the oil into the peanut butter. You need enough peanut butter for 5-6 cracker sandwiches, mix oil, peanut butter and cannabiscompletely, then microwave mixture for 7-10 seconds twice with plastic wrap over top. Graham Crackers work the best, break in half and make little sandwiches of the peanut butter oil and cannabis mixed together. I put the weed butter oil mixture in the fridge for an hour or so. The butter mixture needs the coolness to maintain its integrity and not run off the cracker.
Wrap sandwiches in squares of tin foil, shiny side out.
Place on cookie sheet and bake for 26 minutes.
Each sandwich will have approx 1 gram of cannabis, and this process will extract alot of the thc into the butter and oil.
These will melt your face, be careful.