These are a couple of bugs I've run into during my recent game.

There is a graphical glitch where rivers show up, but they are treated as plains for movement. I've only noticed it for wildlands, and I don't remember how the rivers were acting before the wildland was conquered.

Blood curse is not working correctly. If you cast it on a city, it correctly reduces the population by half, but it does not add that to the sovereign's hp. He is still not able to normally regain health each season. I cast it on Deorcnysse a few times before trying other towns, but there was no change. I had previously cast paragon on another unit.

After first loading a saved game, the Foreign Relations tab is missing the "Relations With Us" screen. It shows up during the next turn.

On some tactical maps, if you move units towards the rear of the map (usually where the archers spawn), you can no longer move the unit to specific squares. You can still right-click to attack an enemy and your unit will auto-move to get in range and attack. In this screenshot, I am not able to move my two air elementals, but they can still attack. 

Miscellaneous: 

Casting Paragon will not always level a hero. If the target has the -25% experience injury, he only receives 75% of the exp to next level. 

I can still use the tactical air elemental summon if I've already used the strategic one.

If I try to use that tactical summon, and the gust ends up knocking an enemy unit into the targeted tile, the air elemental will not be summoned.

http://sharesend.com/rc50l4t4 This is the save file where most of these bugs occurred.