I came looking for "whats up with the filters" in downloads - this is pretty terrible - and if it's not going to be fixed (soon) might save some people a lot of headaches to simply remove the filters so (like me) customers don't spend a lot of time trying to figure out what is wrong. I would debate that not having a feature is more acceptable than claiming to have a feature and it not work.
Another point to call out, as food for thought, missing this feature is a bane to your most loyal customers with potentially hundreds of downloads....especially the ones that sign up for the automatic subscriptions and maybe only download when needed since they have the physical books.
