I have a Bontrager Race Disc Freehub. The rear hub was not spinning freely and was making a grinding noise so I decided I'd repack the rear hub (note: this is the first time I've ever repacked a hub). Did that. On the drive side there was some cone wear and the bearings were rusted. I replaced the bearings and repacked the hub (I'm going to replace the cones in the spring). The wheel/hub spins much more quietly and smoothly than before, though I believe I may have the cones a little too tight.

I would have liked to take off the freehub body while I was there, but I don't have an 11mm allen wrench that I believe I need.

After this I rode my bike for about 20 miles, some in the rain. The hub is good, but now I'm noticing that after coasting, if I pedal with force, the freehub body slips. I've searched the forums, Sheldon's site, and the Park site. Sounds like the pawls are failing to engage (though I still have a hard time picturing exactly what is happening). With all this in mind:

1. What could I, as a noob, have done to mess up the freehub? Could I have driven grunge into the freehub that is gunking up the pawls? (I figure there's a good chance I did something stupid.)
2. I'm on the prowl for an 11 mm allen wrench which are surprisingly hard to find. Any thoughts about where to get one?
3. If I fail to find the right allen wrench, is spraying WD40 into the freehub followed by a light lube likely to help?
4. Without seeing, hearing, or feeling this freehub, can you give me a sense of the likelihood that a freehub in this condition will be workable after cleaning? (Obviously, I'm going to follow the Park site algorithm of clean it, try it, and, if it doesn't work, replace it.)