Don't assume it was YOU that flagged those items. There is a possibility that the items were flagged that way of their own accord. It might be a bug.

Remember that FIDs get re-used. For instance, if you delete a file or a playlist, then create a new file or playlist, the new FID is the same as the old deleted one. In theory, the detailed data of that FID should get cleared out before it gets re-used. But maybe that's not happening in certain versions of the software you were using.

There were other reports elsewhere on the BBS of unusual things like a "plays" count of 65535 when using Jemplode. Perhaps this is related?