You could add an other for each into your first for each. Something like:
For each "Walls"
- set frame to 0
- for each Bios > do the distance check and set frame to 1 where true
For the doors you should probably not use the sine behaviour but just move it out of the way when the player (of an enemie) is overlapping it. You could extend the bounding box to have it trigger when someone is close and then move it back to it's origional position when they aren't overlapping.
edit: here's a capx with the fixxed lighting: dropbox.com/s/g7wfcp8vr61c2g7/SpaceStation.capx