Well, it may be a moot point.

I think I did something bad to the detector. Even though I had it working with the display extended and the whole thing dismantled, as soon as I mounted it in the plastic, it started behaving strangely. Only half of the display lights up, and its power-on-self-test acts a little funny.

I just don't get it, though, everything was working before...

/me messes with it some more...