Hey, thanks for reaching out! Itch.io forwarded your email to me, but I guess my response didn't get through.
First, try to delete the version you downloaded, and use the provided Mac installer. Here's a direct link. It will place the VST3 and AU files in the correct locations. Sometimes the AU version loads when the VST3 won't. If you have any more problems, please open up an issue on GitHub (where I am guaranteed to respond).