Common workflow

1. Store your magnet or torrent to Webtor with POST-request to /resource end point and get resource id in response (it’s just torrent infohash)
2. Select file you wish to download/stream by listing resource content with GET request to /resource/{resource_id}/list and store it’s id
3. Use this id to export with GET request /resource/{resource_id}/export/{content_id} and find suitable export variant and then copy provided url.
4. Just download content with provided url, or use it for streaming.

Download performance

Download speed depends not only on your selected plan, but also on:

1. Your internet connection speed
2. And speed of BitTorrent-peers of specific torrent

qBittorent and other native torrent clients could download content faster in most cases, because they try to download all parts of file simultaneously from best suitable peers. On the other hand Webtor tries to download files sequentially, byte by byte, from the beginning to the end of requested fragment. This strategy makes it possible to do instant streaming and downloading through web browser, but could be less effective in comparison with native torrent clients in context of full file download.

ZIP-archives

Downloaded archives are not corrupted, but it has some special «feature».
It has no CRC32 sums to validate its integrity because it’s created on the fly from BitTorrent network and there is no way to generate CRC32 sum beforehand.
WinRAR is good archiver, but I would suggest to use 7-Zip (you can find link to it below). It also shows CRC32 errors, but without interrupting unpacking process.