Toontrack DrumTracker does not work on my Mac OS 10.5.x

so i thought i'd download Toontrack's DrumTracker demo and give it a shot. but sadly it doesn't seem to work with my configuration. i've got a Mac and an Edirol FA-101 and when i open a drum file in DrumTracker i just get an error saying: "unable to start audio device: Edirol FA-101". I tried to search for a solution but to no avail. that sucks! i was really looking forward to DrumTracker and now this! luckily Logic Express 9 is on the horizon and it will have a drum replacer - among other things. can't wait! i just hope it's not as disappointing as DrumTracker from Toontrack.