I'm trying to close a room I just finished entering, but I received an error message saying "non-zero surface integral." What does this mean and how do I solve this problem?

After the command Check Data has been invoked, EASE calculates the sum of all faces areas. This sum can be considered as a three-dimensional value because every area is added dependent on its orientation in the room. For example two parallel faces with equal areas looking at each other would give zero.
As a result the surface integral of a closed room must also equal zero with a little tolerance.

To solve this problem: In most cases there are two or more faces in the same location. Delete one of them.