You can run the hack with the -40% settings just fine, but it should ideally be tuned on a dyno.

1) try junkyards, eBay, or dsmtrader.com
2) RC makes saturated 440s that cost about $300, and if your car is 96+, u need their adapter clips. I would rather pay ~$50 for DSMs and maybe another $25 or so to have them cleaned and flowtested if need be.
3) You can run a BTM if you want to be able to retard your ignition timing in relation to boost. It's a good tool and will offer some more safety.
4) If you want to be able to increase your boost pressure. Even if you don't want to turn up the boost, a boost controller will usually allow you to rech full boost sooner, since it keeps the wastegate closed until it needs to open. If you run off just the wastegate spring, the gate usually starts opening and bleeding off boost early, which has an effect on your spool.
5) The AFC hack is supposed to be a relatively low-cost method of running 450cc injectors and still being able to tune them somewhat. It's better than running an FMU, but a standalone unit would be ideal. As for the Power FC, you may want to look into Hondata S100 or S200, since they're a bit cheaper.