@Toxaris, given that a Sigil plugin requires Sigil, and Sigil users seeking plugins will come to MobileRead anyway, why not avail yourself of MobileRead's attachments feature?
At least for the Sigil plugin; for your other tools which don't have any relation to Sigil or any other application with a MobileRead support forum, it is of course quite reasonable to host them independently.
It would easily render this
problem moot, as well as perhaps offer a slightly shorter route to using the tool, if someone is discovering it from MobileRead anyway...