Olds,
I would trust the reading on your probes way beyond that thing in the door. For everything excellent about the Bradley, that IMO, is it's achilles heel. You don't have to drop them down through the top vent only. The door seal will form around them & be pretty tight, might see a wisp escape every now & then, but no biggy.
I almost always leave my top vent at least 1/4 open to let the moisture escape. Only exception is when it's REALLY cold & I'm just beginning the process. After the smoker warms up a bit, I start opening it up. The moisture has gotta go somewhere. If you're trying to keep the temp down, it should be wide open.
70 degrees may seem pretty mild (heck, to us up here, that's swimmin' weather!) but if there's not a cloud in the sky, that metal will absorb a good amount of heat. Set it out some day, unplugged, and see what the inner temp is after an hour or two. I'll bet you'll be surprised.
25% volume on the burnt bisquette is about right. That's why if you smoke a shoulder or something for 10 hours, you're gonna need to empty & refill the bowl about half way.
Smoke will come back through the generator if you close the top vent all the way. It's gotta go somewhere. It will even come back through the generator when the top vent is open & the wind swirls a bit. I haven't seen any evidence that this is detrimental.
Regarding the leakage, it's not a good thing as that liquid that comes out will also find it's way in between the box & the front face plate that houses your temp control board. It's an electronic rheostat that will eventually get fed up with that kind of treatment & decide it doesn't want to play anymore.
I have to ask some of the basics, just because, well they've really happened. Is your "V-Shaped" drip pan installed as a "V", not an "A"? Is your meat so packed onto the trays that it touching the sides of the smoker? Are you filling your water bowl to only half full?
Well, I've rambled long enough. Just trying to get you closer to a smoking post with one of these [8D] or these [:p] and not one of these [

]. Hang in there.[

]
Kirk
http://www.chezbubba.com Ya think next time I check into a hotel & they ask "Smoking or Non?" they would mind?