It’s just for presentation purposes, so the character won’t be moving. And yeah, the lighting has been built. Though checking, it was set to Preview. I’ve tried High, but the same issue happens.
Is Nanite for UE5? I’m using UE4.
The hand just has 1 material, though I created an Instance so I could adjust the level of roughness and SSS. They’re looking fine in the mesh preview though:
Yes, that looks ok. You’re right, forget about the nanite comment 
I think… I think I’ve fixed it. 
Turns out you can set a minimum amount for the Lightmaps and a Maximum. Or at least, you can set something in the Min and then in the Light Map Resolution under General Settings in the mesh viewer. So the min is 128 and the one under General Settings is around 256. Seems like a sweet spot. Either way, the weird black patches and seams are gone. ^^
