Slabs are indeed transparent in plan.
You can add a cover fill to them (in their settings dialogue) and then you can use the forward/backward display option or if you don't' want to see those wall in plan you could put them in a layer that gets turned of when viewing the plan but turned on when viewing elevations, sections & 3D.
Adding the extra layer may help with the cutting of the side walls.
The walls are simply trying to trim together - even hiding the layer will not stop them.
But each layer has a Layer Intersection Priority number (set in the layer settings dialogue).
If walls are in the same layer or in different layers that have the same priority number then they will try to trim if the reference lines touch.
Changing the number to be different for each layer will stop them trimming (setting to zero also does the same I believe).
These priority numbers are saved in your layer combinations so you can have the walls trim in one view (say elevations) but not in another (say plan) if you really want to.
Your other option it to trim/cut the walls so that the reference lines don't touch and they will not trim each other.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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