The last issue will take longer to fix and I have a bug report with a meaningless title now.
Reports like this one do not serve the filter list maintainer: filter download failed. It might be an idea to just notify the user that it failed, so (s)he will check his/her firewall rather that having a non-working ABP. This also saves the list maintainer some time (as it probably isn't the first thing a list maintainer looks at, so (s)he might first try to figure out what could have raised the ad for the user, before (s)he finally notices the download failure)
Also mentioned here before.