In order to play soundfonts, use (qsynth.sourceforge.net) qSynth along with (midiox.com) midi yoke. Configure qSynth to load the soundfont you have and make it get input from 'midi yoke 1' (something like that, or any other value for that matter), and configure NWC to give output to the same 'yoke'. Or, you can use timidity++, but it's 'very' old. BTW, the Titanic soundfont is pretty good. If you want to check it out, go (instrumentsvirtuels.free.fr/freeware6.htm#titanic) here, halfway down the page. You only need part 1, I think. part 2-4 is the same thing, but is harder to extract for some reason.
It might be a lot to download, but it's free and well worth it!
-Static
EDIT: Sorry, you'll have to copy-paste the links. I can't use working ones because I have to upgrade
EDIT2: Direct links here. qSynth windows binary - sourceforge.net/projects/qsynth/files/qsynth%20(stable)/0.3.5/qsynth-0.3.5.tar.gz/download MIDI Yoke download page with instructions - midiox.com/myoke.htm#Download Titanic sf2 - instrumentsvirtuels.free.fr/part1.rar