Hi, 
I've revisited the real walls concept for TLD using the Ground Tactics 2.1 mod. 
Since the soldier path finding has been greatly improved ... it appears infantry units will end up together, even after being separated due to complex routes through doors and windows. 

How real walls effects game play 

Movement: 
a. Soldiers must enter/exit buildings through doors and windows only. Buildings side be side (in a row), but separated by exterior wall elements ... may require way points on side of buildings that the player wants soldiers to transit ... since buildings of this type need to be exited before moving to next building. Without way points ... soldiers decide which side to transit. 
b. Soldiers can move through Interior walls (coded this way, due to the complexity of some buildings interior wall floor plan). 
c. Movement through bunkers now seems more reasonable, and no soldiers getting stuck in the high hindrance, multiple layer bunker wall element. 

Targeting regarding Bunker Walls: 
a. All Line of Sight is blocked for bunker walls: 
a. Soldiers firing out of bunkers must be positioned in front of windows/doors in order to get L.o.S. 
Most of the time soldiers will line up in front of windows and doors, but occasionally a move order may be required to get a specific L.o.S. 
b. There is no longer the ability to fire through corners of bunkers. 
c. Angles of fire are reduced also, which require more detailed arrangement of infantry units. 
d. Not all soldiers of a unit may be able acquire L.o.S. (at the same time) when firing out of a bunker 

Targeting regarding Interior Walls: 
b. Since interior walls don't permit Line of Sight through ... soldiers can retreat behind an interior wall for cover, from fire coming from outside the building. 
c. Interior walls separate rooms in some buildings ... therefore different tactics may be required. 

Problems: 
a. I saw one map so far in TLD with no windows coded in buildings ... Juno. Therefore soldiers only enter/exit through doors. 

Overall, this method of simulating walls seems more realistic regarding movement and L.o.S. 

in summary: 
1. Soldiers can not move through exterior wall elements 
2. Line of Sight through exterior walls when adjacent, except for bunker walls 
3. Interior walls: soldiers can move through, but all Line of Sight is blocked.

Changes for v1.1

List of changes: 

Exterior walls: 
1.Move through: can not enter terrain 
2.Protection: values doubled (for extra soldier protection inside buildings) 

Interior walls/interior doors: 
1.Line of Sight: Block all, even adjacent 
2.Protection: values doubled (for extra soldier protection inside buildings) 

Exterior windows and doors: 
1.Move through windows: 40,35,30 
2.Move through doors: 30,16,14 

Large hedgerow: 
1.Half Track/Tracked: can not enter this terrain 

Small hedgerow: 
1.Block Line of Sight, except when adjacent 

Bocage: 
1.Pushed vehicle: 64 instead of 0 

Sheet metal wall: 
1.Changed Line of Sight to: blocked, except when adjacent 

Military Equipment and Civilian Equipment: 
1.Can enter terrain ... helps stop soldiers from getting stuck 

Crates: 
1.Can pass through, soldier low ... helps stop soldiers from getting stuck 

Bunker wall; 
1.Move through: Can not enter this terrain 

Bunker window: 
1.Protection: values halved 


LSA Elements file v1.2 
List of changes: 

Exterior walls: 
1.Move through: can not enter terrain 
2.Protection: values doubled (for extra soldier protection inside buildings) 

Interior walls/interior doors: 
1.Line of Sight: Block all, even adjacent 
2.Protection: values doubled (for extra soldier protection inside buildings) 
3.Move through Interior walls: 30,25,20 


Exterior windows and doors: 
1.Move through windows: 30,25,20 
2.Move through doors: 30,18,16 

Large hedgerow: 
1.Half Track/Tracked: can not enter this terrain 

Small hedgerow: 
1.Block Line of Sight, except when adjacent 

Bocage: 
1.Pushed vehicle: 64 instead of 0 

Sheet metal wall: 
1.Changed Line of Sight to: blocked, except when adjacent 

Military Equipment and Civilian Equipment: 
1.Can enter terrain ... helps stop soldiers from getting stuck 

Crates: 
1.Can pass through, soldier low ... helps stop soldiers from getting stuck 

Bunker wall; 
1.Move through: Can not enter this terrain 

Bunker window: 
1.Protection: values halved