One problem that I have encountered is not new. I encountered the same thing in the last 2 games as well. When restarting the game, unless I completely exit to my desktop, after a few turns the game crashes.

Another I have run into is units becoming unresponsive. This seems random. Every now and then the game will appear fine yet none of my units will move. Even if i click the turn button nothing happens. 

As others have mentioned I too have encountered units not appearing in combat along with a display error for the grouped units selected where I have 5 units yet the group icon olong left side of page shows 4.

When fighting the giant worm in the cavern (forgive my short term memory for not remembering his name) the graphics would break up each time i would mouse over the enemy and return to normal after taking an action.

Overall aside from these I am loving the game so far. I can't wait to check out the finished product.