Hey hippie
I'm not 100% sure and I am just going by the manual,because I just looked this up today for myself. I believe the only sound file format that FPSC reads is .wav. You can convert your file with
audacity a free sound program that reads and writes .ogg .wav and .mp3.
Once you have the right format it should be quite simple,just make sure to put the sound file in your audiobank folder, and if your,say, using a sound zone,make sure to lead it to the appropriate file.(right click the soundzone)And it will work in test mode.
Hope that helps