Hi Steve,
The bug with clicking 'cancel' in the race creation menu still exists in 1. 6. 3. To confirm this, I installed a fresh version of 1. 5. 1 then patched it to 1. 6. 2 and then to 1. 6. 3
Repro steps are:
1) Open game info screen
2) Click 'New Game'
3) Click 'Create Game'
4) Click 'Cancel'
A new game will be created regardless and after completion you'll be met with a blank map and scrolling with the mousewheel will throw null reference exceptions at function #1616.
Thanks