@dhdurgee: I have no idea if magazines are actually shipped as KFX (they certainly didn't use to), but if they actually do, then, no, you're probably screwed.
Not that you're possibly also screwed even if they're shipped as Mobi/KF8, because I'd imagine those to be encrypted, so you'd probably have to do more than mess with metadata (which I'm don't remember if we actually can on encrypted mobis anyway).
I'd be glad to have a look at one of the file to see if I can figure out what trips the script though
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