I do use that. I see how I missed finding that in my search for the settings responsible, I commented out the fimfiction section of my personal.ini but left the global stuff like that alone. Sorry about the incomplete repro steps for an obscure bug like this, hope it wasn't too much extra trouble tracking it down.
I don't mind having corrupted source data downloaded and saved like that, it's easy enough to remove later if I notice it and it's a bother. Better than trying to recover from corrupted *processed* data if I discover it once the original source is no longer online.
I'll give the attached version a spin.
Edit: Yup, it works. Thanks!