Ill just add that click torque wrenches are supposed to be stored with the torque value set to zero, the head should be rocked back and forth a few times before use to distribute the lubricant through the gears and torque wrenches should be calibrated now and again. Not that anyone does it.  i Prefer the push button kind myself. But they are quite expensive.

What little I know:
I don't know how many torque wrenches I have. Somewhere between a dozen or two. American, German, Asian, etc.
I've had pretty good luck with all of them. None were low end garbage.
Spent anywhere from $80-$400 on them.
Taught motorcycle maintenance for 36 years. Saw lots of busted fasteners.
So...
A torque wrench is a measuring device. Most meters are most accurate in the top 90% of their range.
Think of an analogue volt meter. Imagine you have one that goes 0-1000 Volts. You wouldn't think of using it to read one volt, right? Needle would barely be off the peg.
Likewise with torque wrenches. You'll need two-one for the little stuff, one for the bigger stuff. Maybe Inch pounds for the small stuff, foot pounds for the bigger. Have some overlap so you aren't using the bottom range of the bigger wrench.
You have a free way to check the calibration of your click type torque wrench. Nice, because when I send my Snap On ones in for calibration they charge $75 to do that.
Take the bend beam torque wrench, find an 8 or 12 point socket that fits on it and also fits the male end of the click wrench. Set the click wrench for a number more than 10% of it's lowest reading. Turn the wrenches against each other and watch the bend beam for when the click wrench goes 'click'.
Maybe check two readings.
Done.
As for the 45 ft/lb pooching the sprocket studs, welcome to the club. After way too many students with Suzukis buggering the sprocket studs of various models of Suzi-Qs, I finally told them to use blue Loctite and only go to 35 ft/lbs.
The comment earlier about lubing the threads is valid. I usually use nothing more slippery than WD-40 on threads, unless they see a ton of heat or pressure, then I use Anti-Sieze. Engine oil will completely fool your torque wrench as it makes the fasteners too easy to turn.
This is why some companies (HD, BMW) use torque angle specs. Basically you take the slack out of the fastener, then you turn the wrench a specified number of degrees. Much more accurate.
What little I know I gladly share.

Try this too:
https://www.youtube.com/watch?v=uFDUsUEQrL0

I have one in ft lb & one in in lb trust them more than the click type !
Nothing to malfunction !!!!!

Kris,
They've done studies, and very few people are born knowing everything. One of reasons folks read this kind of page on this kind of forum-to learn.
So, those of us who have a clue try to pass things on to those who don't but would like to.
-Armen

Most of us learn from our mistakes.  Some of us learn from other's mistakes too.  

Thanks everyone. Armen, you've got some interesting stuff there. I wish I had known this all before I screwed it all up. I'll look at your links. I'm getting ready to call it a night. It may have been that I ran out of threads. The omission of washers was an unfortunate oversight. Maybe running out of threads causes the bolt to strip unusually easily? However, from what Armen said, it might have happened anyway. The other fasteners seem okay. I took them out. I wonder whether I should buy one bolt, all bolts, or no bolts.

You know... with this kind of crap, I wonder if I'd have been better off tightening them by feel and not even bothering with the torque wrench.   You use a torque wrench to get it right and do the opposite... You don't stop where it feels okay. You may not even pay much attention. You go for the number. And the number is a trap.

It has crossed my mind to just buy another used hub and sprocket. Then I can get all the bolts, an extra hub, and another sprocket to play with.