@Radagast - I was hoping to force carbonate it, rather than do the usual sugar method when bottling. My plan was to do basically the same thing you describe - put the psi high for a couple days, then lower it over a few more days. As for setting the CO2 then turning off the tank, no. In fact, I didn't realize I could - or should - do that... I thought I had to leave the CO2 pressure from the tank on the whole time the beer was in the keg. And yes, I bled out the entire CO2 tank.
@Voodoo_Donut - some did leak out of the keg into the kegerator, but it wasn't that bad... it didn't gush out. I did have my beverage line hooked up while this process was going on. I never thought about leaving it unattached until ready to check it after force carbonating.
@ Sneezles61 - Oh yes, I cleaned everything. I'm really paranoid about contamination, so I pretty much tend to over-clean most of the time, without really intending to. I didn't twist or pull the lid though after connecting the CO2; again, that's something I didn't think of (comes with experience I guess).
I did try the soap and spray bottle method to check for leaks, but I'm guessing I didn't do it well enough at all. Once everything was hooked up, I put the psi up to about 30 (as I recall, close to that at least - it's been a while since this happened). I noticed that the psi wouldn't stay there, it would slowly ebb off from 30. So I kept trying to make sure the seals were good and then I'd try again with the same result. In the middle of all this I was trying the soap / spray bottle method as well. The entire hose setup was connected.
Is it possible that the CO2 could have leaked from the tap itself? Or does that seal well enough that it shouldn't have an issue?
And I'll definitely look into Keg Lube - thanks for the tip there!