I agree, the HID kit should work perfectly right out of the box, but sometimes it requires a battery harness because the power supply to the lights is slightly restricted from the factory. I think I read somewhere that the reason is because some numbskull driver somewhere couldn't figure out the difference between daytime running lights and regular low beams and, as a result, there was an accident at night and a lawsuit and now car manufacturers have to slightly dim daytime running lights. They cut the power to them just enough so that when it starts getting dark, people should reailze they need to turn on their low beams so they can see.
To raise your headlight cutoff beam, there should be a small (10 mm?) bolt (I think they're plastic and clear/white?) behind each light. I remember it was sort of tight getting to them, but I was lucky enough to have access to a flat ratcheting wrench. Otherwise, I'd have to put a regular wrench on, twist a tiny bit, take it off, and repeat a whole bunch of times. Like turmic said though, be careful not to raise them up too high because I've gotten flashed a couple times now too. I don't think it's necessarily because they're too high - I have them just high enough so I illuminate the ground in front of me if the road is flat (before I adjusted them, it looked to me like the lights cut off 30-40 feet in front of the car and everything in front of that was dark). I think I get flashed occasionally because of the intense glare that's created by my headlight housings since they weren't intended for HIDs from the factory, but I can see great so that's all I really care about.
07 WRX (Albins 5MT + Blouch 20G)
Jorge Carrillo Tuned (365 whp/340 wtq)