Amazingly, I've found the combination that allows for crisp texture import from Qubicle --> UE4.
(The below assumes you've already imported the .fbx to your level in the editor. This is pretty easy so I'm not spelling it out here.)
In the texture editor for UE4, first open the Sphere-ish example and then look at the lower left hand corner for the source texture map.
Double-click on that, and set the following settings: Compression Settings --> UserInterface2D (RGBA) then change Level of Detail --> Texture Group to 2D Pixels (unfiltered) Save/Apply these changes.
(Edit: You may not need to change the below, I tried it with just the setting above and there were no errors. I might have had an error from something else I was trying to do before... so take the below as optional...)
Now, in the texture editor itself that has the node graph with all the fancy connections, select the Texture Sample node, and you'll see in the lower left-hand corner some new options. Change Material Expression Texture Base --> Sampler Type --> Linear Color.
If this is set just to Color, there will be an error and it won't work properly. Save/Apply these changes and rebuild your scene which will recompute lighting and texture changes. There it is!
You may have some lighting issues, where the near perpendicular planes seem darker than the ones facing the sky, but that can be tweaked a bit by adjusting lighting angles and other parameters I haven't gotten into just yet.
Hope this helps someone....