Experienced two pathing problems... one was was going around a lake, my units (who were going to a point a fair distance away) walked through some water tiles. There was a road next to the lake, but no changes to the tiles since they started their journey (i.e. I didn't use any earth magic to sink land tiles into the water... if there is such a spell. Haven't really played with terraforming spells yet.) 

The other was a unit spawned in a water tile next to the city that trained it. I was able to pull them out and save them from drowning.

I'll see if I can procure some save files later that demonstrate one/both of these problems.