I love that beer. I brew a lot of brown ales and have never attempted this one but I think you could get close with this and then begin to tweak:
6gal postboil
1.054 OG
85.5% two row
5% light munich (10L)
5% crystal 40
2% crystal 90
2.5% chocolate
25 IBU bittering - 60min
.5oz Amarillo - 10min
.5oz Amarillo - 0min
1oz Saaz - dry hops
Pitch with California Ale
I realize this isn't 7 malts, and I'm really only going off my taste memory. But my thoughts on that beer are it's not as roasty as many brown ales out there, it has some light fruity malt and a little toast, and the citrus hop is subtle but apparent. At the very least I think this will yield a tasty brown ale and then you can taste them side by side and begin to change things.