The border lines (red in my case) disappear sporadically, so it no longer shows the lines around cities and outposts. The only way to get them back is to exit the game and come back in.
Also, sporadically and for no reason I can determine the resource (food,magic,production) disappear from tiles. And there's no way to see what they were. If you click on a tile, you should have it show the resources as well as whether it is settle-able.
