Broken midtextures in Techno Hill Act 2

These midtextures seem to be pushing me back for some reason. I've only encountered this in this one section.

This is due how solid midtextures get their attributes. Usually taking from the sector in front of it, in this case, the midtexture is acting like the slope beside it.

mentioned in merge request !2447 (merged)

mentioned in merge request !2454 (merged)

closed with merge request !2454 (merged)

mentioned in commit 5d72b438