Torrent files never work?

occasionally i will get a torrent to work. But recently I tried downloading a torrent with 234 seeders and like 6 leechers (Just guessing) and it still wouldn't work. I've used a couple different programs like bittorrent, vuze, and transmission (I'm on an imac g5). On transmission, I will get an error after awhile saying it cant retrieve trackers. I've looked at the comments on the torrent file webpage and one's that are recent are saying they have no problem download. Could my problem be, I need to open ports or something because I've had a couple computers and not until I've gotten this one has it had any problems. Please help, I need it to download a free trial for a version of software that works on g5 but is no longer available for download on the developers website.