Sorry Rob, it worked for me in all variations, that's why I thought it may have helped you. Mark at Pinkfroot has told me that he has also replicated it so is now working on a fix. Hopefully they won't be too long.
I managed to replicate your problem. To solve, use the Map drop-down menu in the top right corner (where it says Map Database About Contact) and choose Settings. A new menu will open on the left. Use the Map Dimming slider to make it brighter then return it to where you'd like it...