The overlay always shows 20/20 and the red meter stays full. It never goes down and the numbers never decrement. You can see the hearts in the background changing however.

Are you playing singleplayer or on a server? The mod doesn't work right if it's not on the server side. Also, have you changed the config file at all?

I had no idea it was meant to be on the server. I felt like a client side only mod. Yeah, playing on a server. Might want to add that it needs to be on both client and server.

I thought I mentioned that on the CurseForge page, looks like I didn't. Oops. It needs to be on the server to get the player's actual max health, which doesn't sync with the client sometimes (it just assumes it's 20). Still, I should probably make it so it will work client-side only as well.