Limewire opens multiple times for torrents

[ShifterCat]

I seem to have a unique problem: every time I download a torrent file, a new LimeWire opens up. I've often found (using "programs running") that I have two or more instances of LimeWire running at once because of this. It slows my computer to a crawl, and so I have to shut down all but one of them -- which sometimes means losing the torrents I was trying to download.

If it helps, I'm using Windows XP with automatically updated Firefox and LimeWire 5.1.2.

Thanks in advance for any help you can give!