I found the culprit.
It was Wordpad. Eeeeeevil Wordpad.
Amongst other annoying glitches, wordpad is possessed by the Demons of 10ptyness. When you open your file in Wordpad it is automatically downsized from 10 to 12, which you don't notice because you're on the laptop and so inadvertantly piss off good and deserving editors with your teenytiny letters.
I say FIE unto Wordpad. How much FIE? Enough FIE that I have banished it from my toolbar in favour of a freeware wordprocessor called AbiWord. It's as shaky as Heck, tries to load a nonexistant dictionary every time you open a file, and crashes altogether if you try to use the Help... and yet strangely it still sux0rz less than bloody Wordpad. I'm running Star Office over on the big 'puter, of course, but Lurid needs that to shoot Klingons.
Edit: I've just resubmitted the story that got rejected yesterday to a different market. The ed. of the rejecting zine was right: the ending was too weak. I've altered it, and I think the story as a whole works way better now.