Transmission

I really like Transmission a lot - it's hands-down the best Mac BitTorrent client out there. However, there is one behavior that just drives me up the wall - it will allocate space for unchecked files that are adjacent to active downloads. I understand that, as part of BitTorrent, some pieces will span two files, but instead of allocating space for a file I asked it not to download, I wish Transmission would simply discard the unneeded bit rather than allocate a file that could be hundreds of megabytes if not gigabytes in size and waste space on my drive. If I decide I want the file later, I'm more than happy to download the piece again. Does Transmission offer this capability? Is there a hidden setting I can change?

As rb07's pointed out, this appears to be a duplicate of this thread, so I'm going to lock it. Please make any followup posts in the original thread instead. Thank you!

Also, thanks for the kind words about Transmission.