The first was adding in some sunlight blockers around the edge of my walls as light was just leaking through very slightly on the corners.
Secondly I upped the lightmap resolution on a number of assets to sort those shadows out and make them look better.
After I rendered out my videos I did notice some specular glitches on metallic/glass surfaces, this actually came down to my roughness being too low, I upped this to 0.2 (Instead of using the input maps) and it worked out the problems I had.
I just now need to re-render out my video, tidy up my level a little more then package it. I've also made a start on getting all my binaries together and writing up my development documentation.
