Sorry for taking so long to get back to you.
It's not that I suspected Voxal wouldn't work with Curse, but that I wasn't going to take the chance at finding out the hard way. Fortunately, I managed to test it with someone I trusted implicitly, and found that it does in fact work with Curse Client.
So, thanks for your time, and I'm relieved to find that I was mistaken on this issue.
EDIT: As far as my comment in my original post, "Voxal doesn't look like it recognizes it (Curse)," when I begin a program like Mumble, a message appears in the Voxal window, "An application is using the microphone." That didn't appear with Curse. However, I did find that the chosen voice modification was applied to my voice when I tested it with the trusted friend.