Difference being that with those there is a work around - either using Account Management or by getting refunded MS points through the helpline.
Thinking about it, I might try downloading the file with a different live account. See if that works.
Mine is a replacement/refurb from MS. I don't remember downloading the media support, I'm just assuming I must have done so to provoke this.
EDIT: that did the trick. A different account allowed me to re-download the file with new rights for my current console. I can now play vids offline.
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