I also put together a quick tutorial with images for anyone having trouble trying to setup their landscapes inside of the engine! This will help you with getting the layer info setup and using the correct materials for the landscape. Enjoy and let me know if anyone has any questions!
All of the mud and grass textures include both versions with puddles already in them and versions with no puddles. So that way you can choose which one works best for you if you’d rather have it in the texture or paint it on yourself later. Also whichever one you think looks better, it’s all up to you! 
Lastly, as a “Pro-tip” If you paint the puddles layer onto your terrain at a low strength/opacity at like 0.05 or 0.1, you can make the materials just look wet like if they are near the river or a lake. Just thought to throw that out there 
