torrents

Using qBittorrent (v4.6.5) and Mullvad VPN (post their removal of one's ability to port-forward) I am able to seed a torrent that I have downloaded; however, if I create a torrent locally and try to share it, it will not seed. It's only when I disable the VPN that it will seed. I have not port-forwarded manually — qBittorrent is using UPnP (which I assume Mullvad VPN blocks).

I don't understand the difference, though. Why am I be able to seed an established torrent, but not a new one? Afaik, both cases would need to accept incoming connections, which would require a forwarded port.

I'm sure that many are aware of the big names like QxR, UTR, etc. They always add their names to the filenames so that people know that its their torrent; however, this isn't exactly a secure method for people to know that it is indeed their torrent, as anyone can easily impersonate one of those big names by renaming their file. Why don't people just add a signature to the torrents that they release? That way you can verify if the file really does belong to who it says it belongs to. Of course, this would also necessitate some means of distributing a public key.