Woz, depending on the presets you put in for your system you will get different numbers, and this is a good thing that way you know how you have to adjust recipes to get your intended beer. What I do when building recipes in beersmith 2 is pick your equipment profile, set the boil time and efficiency and everything then just put in 1 lb of each grain and click the adj pectentages button and match your clone then click the adjust gravity button and crank that up to your intended OG. For this recipe I needed like 3.5 extra lbs of pale malt and a little more of everything else to get to that OG on my system. If you are going to brew this I would target 6 gallons into the fermenter because that is what I did and I ended up with only 5 gallons in the bottling bucket after dry hop and grub loss. To ferment 6 gallons just use two carboys and fill them each with half the wort. Also, no need for secondary, I just dry hopped in the primary after one week. Hope this helps!