Custom effect preset doesn't show but it's in the presets xml file

When an effect preset I had saved last year failed to show up in the effect today, I looked to see whether Audition's effects presets xml file had been changed. But the effect I saved is listed in the effect presets xml file, but it still doesn't show up.

Why would this be? And how do I get Audition to "see" it again?

This is CS6 on a Mac running OS 10.8.5, and the effect in question is Waves Gold Q10.