Intro to Texturing: Intro to Substance Materials

Increased directional-light's intensity from 1.0 to 1.5 and reduced reflectivity for each surface.

It was at this point there was an error at the baked texture stage, where you reassign this texture to the walls and floor. Every-time it was reassigned the 'UV Divisions'  returned back to their original settings.
Additionally, throughout the working of the tutorial, there was a problem, in that new changes did not update in the viewport, so I had to flip continuously from editor and rendering to see every alteration made. Under Simon's suggestion, I tried both 1- checking the viewport was working in 'Viewport 2.0' and not 'Mental Ray'...  and then 2- deleting the old preferences, to help solve any form of corruption that may have occurred.
However this didn't work, so I had to start from scratch.
There's also a problem in which hovering or passing the cursor over 'Render' in the 4 panel view causes the program to suddenly crash, so I have to keep orienting the cursor around that screen to avoid hovering over it at any point. This can be troublesome if the reason for heading to the top left was to save, and so I keep accidentally having to revert to slightly older files when saving doesn't go to plan.

2nd Attempt:

'Final Render'