Everything related to the integration for SketchUp.
By JDHill
I was able to locate online an HDRI of the same name (Stonewall_Env.hdr) as the one you are using, and I don't see any problem; try changing the Image Based > Background > Scale U/V values to 2, and you should see a different portion of the HDRI through the windows (I am using the "Scene 2" scene).

Or, try using one of the HDRIs from the C:\Program Files\Next Limit\Maxwell Render 4\hdri directory (maybe it is just the copy I was able to find using google, but this Stonewall_Env.hdr is an extremely low-quality HDRI).
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