There is a good thread about standlights on Candlepower forums. And Pilom is the gold standard. You might also want to look through the mtbr forums diy section. If you are using a single led or two for that matter, you don't need Circuit 12. Circuit 12 improves low speed performance for a large number of emitters. At low speed, the dyno can't generate enough voltage to overcome 12-24v Vf of a large number of emitters. Circuit 12 does not incorporate a standlight.

I just got the Cutter XPE triple. 3 emitters on a 20mm board. Haven't decided which circuit to run it on.