AI froze late in the game after it ran out of roads.
One of the AI controlled opponents in a single player game got stuck while thinking with the ... dots. The AI player played the first of two road building cards and then placed two roads. The the same AI played a second road building card on the same turn. It placed one additional road and then this AI ran out of roads!
--The AI ran out of roads and couldn't place a second road for a science development card. This is when the AI got stuck and just paused the game thinking.--
The AI It still had all its ships in hand but no settlements/cities on the coast to place them. So It couldn't place those either.
I tried quitting and continuing the scenario, but the AI still got stuck on the same card trying tp place a road it didn't have.
For now, I still have the scenario available to continue, if the developers have a way of examining it.