I think you will find the "a-wall-ext.new" layer has a different index number in the model file and the documentation file.
I believe the layer combinations use the index numbers rather than the names.
You really need the two files to match perfectly -i.e. they should both really be generated from the same template file.
Try to copy both the layers and the layer combinations over in your AAT file.
And use "Overwrite" and not "Append" when transfering the info.
Experiment on a copy of the documentation file just in case you suddenly find all your walls on the wrong layer.
I think the elements stay attached to the layer name though so all should be good.
Or maybe others that play with this more have a better understanding.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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