Actually the discoloration is present in the standard package without any changes for CoreRPG, I use the wood theme if there's a slight coloration difference which I don't believe there is.
As for the changes, it I just basically hid the tabs so the underlying data structure is there, just hidden. I'll also mod in to hide the 'portals' tab.
It's more an immersion issue with the players so when they use locations, they aren't presented with an overly long directory to keep things compact.

