TE: Impossible portals are "possible" (but actually still impossible)

[Joey79100]

Impossible portals are "allowed", but fail to be created, with a (more or less) obscure message (as in: it's not obvious).

Open this project file: Mountain-TE_portal_issue.zip

And reproduce these steps:

1. Navigate to Room 5.
2. Select the middle sector in the North wall of the room (Global area (52, 35) / Local area (5, 10)). It is marked with an orange texture for easy recognition, but here are screenshots just in case:
3. Click on the Add portal button, like if you wanted to make a door to room 37 (wall segment marked in orange as well). The Create portal window gives you the possibility to select room 37. In fact, this should be impossible, because there there is 1 sector of emptiness between these walls, but TE seems to allow you to do it.
4. Click Ok to create the portal. You will only get the following alert:

Fortunately nothing bad happens.

I was just confused, because I didn't realize there was some space between the rooms, and I thought the portal should have worked but failed. It's just that by default, TE seems to search a bit too far, which allows the user to try to create portals that just aren't possible.