I just made an updated version of Tic-Tac-Toe as a .mis mod! This means that it's completely contained in interiors/ and missions/, so it should work in just about any mod that contains the original MBG textures and interiors (or replacements for them). It's been tested in MBP Mac and Windows; leaderboards are still accessible after playing it.
Link: www.dropbox.com/s/rdnbgb7h5m135z0/Tic-Tac-Toe.zip
Link: www.dropbox.com/s/rdnbgb7h5m135z0/Tic-Tac-Toe.zip