How does the pedal feel? Firm? Mushy?
It's been a little over a month since your swap so that means it is a very small leak (unless you have been constantly refilling your fluid). This means that pumping on the brakes probably won't reveal a leak.
Check your brake pads. Your'e using drilled and slotted rotors with EBC pads and 17" wheels, which means your'e generating more heat which causes your pads to wear more. Also, the 17" wheels require a little more stopping power (= more brake heat) because the wheel has more leverage/torque on the brakes. If youre stopping like a maniac then your problem could be that you're wearing the pads low and/or boiling the brake fluid. This would cause a change in fluid level.
What kind of fluid are you using? Boiling fluid is dangerous because the fluid turns into a gas which creates bubbles in the system, thereby causing loss of pedal pressure and fluid level.
Here's what you should do:
Fill it with fluid then clean around all of the fittings (including the base of the fluid resevoir) then check again for leaks. Also check the caliper pistons for a bad seal or a slow leak and check the pads for excessive wear and replace if necessary. Then drive it for a week and check again for leaks. If there is still no sign of leakage then the only other place it could be leaking from is at the back of the master cylinder, which also means the brake booster could be filling with fluid (I've had that happen before).
If you still have the problem then flush the brake fluid and replace it with high temp fluid.
If changing the fluid doesn't solve the problem then change your rotors/pads to stock. It's great that you have slotted/crossdrilled rotors, but like I mentioned at the very beginning of the thread, stock pads/rotors work best for a street car. This is because crossdrilled rotors have less surface area and require a harder pad which creates more heat. They're great at the track when you're generating ALOT of heat, the holes/slots remove gasses and cool the brakes, but not so great on the street.
I'm using the stock Integra system and haven't had any problems.