My torrent isn't moving and there's a lock icon... How do I fix this?

The padlock icon appears by private torrents. Tixati is not allowed to use DHT, PEX and LPD for that torrent, these are alternative ways to obtain peers addresses, Tixati uses only tracker for that kind of torrent. Other than that, it's no different than regular public torrent. You should be able to download and seed it as usual, as long as the tracker is responding and there are other peers to connect. You can do nothing to remove the padlock. If the torrent is stalled, wait a few days, maybe someone shows up and you will be able to complete. You can also request reseed on private site, from where you get the torrent file. If that doesn't help, try to find a public torrent with the same content.