While on the plant part of the mission where you have to scan 3 plants, the ground seems to be "eating" my teammates as well as some enemies. My teammates are rendered useless while the enemy is able to fire at me through the ground O.o With this humanoid eating planet devouring my team, I find myself impossibly out matched to fight off the local enemies =(
that old buggy map is still in the game? yeah... just beam up, drop it, and find another one.
If you keep looking you'll find a spot where an anomalous data signature is embedded in the ground where you can't scan it.
Th issue with the map seems to be that spawn point were calculated using the geometry of a different map. As you mentioned, some enemies spawn under the ground. And there's a few spots where the surface of the ground and the surface you walk on aren't the same thing.