Obligatory disclaimer: I am a total rookie, just looking for some help. Hope this is the right place!
I’m an architecture student exploring UE4 as a possible tool to add to my repertoire, but I’m brand new to UE4. Can anyone help me with this artifact issue? The screenshot also includes Lightmass settings. Basically I am trying to model three rooms that have strip lighting along the edge of the floor and the wall. I used rectangular lights for this. However, I learned pretty quick that one cannot have more than 3 overlapping stationary lights. Thus some of the lights are static. But what is up with the artifacts? I’ve tried a variety of Lightmass settings; I’ve read here and there that some of the champions in UE4-archviz use a Static Light Level Scale of 0.1 but to be honest, setting it that low causes nothing but problems for me…
Other information about the scene, it was originally modeled in Rhino 6. Unfortunately, no option for multi-channel UV-mapping there. In other words, I’m having to rely on the auto-generated Lightmaps. They look fine to me in the Static Mesh Editor but then again: I don’t really know what I am doing yet in the UE4 environment. Materials are based instances of Megascans Master Standard, materials themselves are mix of the Megascans library, some self-made in Substance. Everything in the scene are planes… not solid meshes. That a problem?
Anyway, if anyone could help me out, that’d be amazing. Got deadlines you see 
thank you in advance! Oh and sorry for the poor image quality: It won’t let me upload an image larger than around 300kb…
