No It does not need to download again to start seeding a file.
In your case I believe the torrent file is not in the same folder as the file you want to share. This is a good rule of thumb. When you create the torrent file, that the torrent is in the same folder as the target file( the one you want to share.)
Upload it to Useekfile and redownload it, all in the same folder. The way I view torrent files as pointers to a file. They contain the information as to exactly where the "target file" is stored on your hardrive. If you move the the file after creating the torrent, the bittorent client (utorrent) won't know where to look for the file and assume it is a new download.
Hope this helps
Let me know if you need some more help.
