Most of the HUD mods replace the HUD's textures themselves. That means that every time Klei updates the HUD's textures, those mods'll have to be updated too. This guide will help you make a mod that changes HUD without replacing textures!
Download my HUD skins library from here
Copy hud_skins.lua file to your mod's folder.
In your modmain.lua file paste this line:
Create a scripts folder with img_override_data.lua file in it.