How can you extract or recover files from incomplete torrent download?

If it's a public tracker then enable dht and that may help you finish it off. Failing that you could contact the uploader and anyone that has completed the download and left a comment and ask them to reseed it for you.

yea seeders like to jerk sometimes and log-out altogether and never show again

i really hate this

was trying to D/L new super Mario bros and file size was 4.5gb it toke a day to get 55% and next morning it was stuck at 0kb/s and they never came back

but advise when u are picking files

don't pick the ones with low seeds if there ones with high seeds[because higher seeders will definitely keep the torrent up more than low seeders] even if they have more leeches

You can't. Better find another working torrent. Note how seeders and lechers it has.Higher number,higher torrent quality.

The data that you downloaded will be wherever your normally downloaded torrents go.

But you can't get the data you never downloaded unless you link with another seeder

you know torrents can be resume anytime and can be download fully. so you have to resume and download 100%.then you can extract file. otherwise you can't.