I've attached a couple of layouts I've just done, 1 with and 1 without the floor/roof.
The sizes have come from Dave Cushmans site based on the national hive.
I've not bothered with the rails for obvious reasons.
The is is 10mm gap between each part and the 2439 x 1219 are the metric conversion of 8' x 4' as I don't know what width of blade or cutter would be used to cut it up.
Good luck taking this into B&Q and handing them this to cut it for you.
I'm sure you will be very popular.
The cutting list.pdf has the sizes for each panel on it for each component.
Hope it is useful but can adjust it if you need it.