Custom Sound Files

[UberNoob]

Hi again, I need a bit of help with some faceposer stuff. I've been trying and failing to import a custom wav into it, but no matter what I do, faceposer won't recognize it, so it doesn't show up in the list. I've been following Kyl's excellent tutorial on custom .wavs in faceposer, but despite re-reading it three times, I have not been able to find the problem.

Any help with this problem would be appreciated, so thanks in advance!