looks nice this building
for assign the walkable and no walkable cells in the building you must edit the "cellmap value" parameter in the xml
1=no walkable (wall), 0=walkable
For example for made a 3 cell building with a door in each one of his walls:
<cellmap value="true">
<row value="101"/>
<row value="000"/>
<row value="101"/>
</cellmap>
For made a 4 cell building with only 3 doors:
<cellmap value="true">
<row value="1011"/>
<row value="1011"/>
<row value="1000"/>
<row value="1011"/>
</cellmap>
You can't put floor in your buildings... the units don't know where is the collision