With Building Material Intersection Priority Numbers properly set up, these details should clear up pretty nicely.
For that detail you are showing you could model it out of a Complex Profile. The horizontal stretch zone of the profile should be at the top of the details so you could model the stepped basement wall using a single profile. You would have to place 5 pieces of that Complex Wall, each with a lower base. If you set up the horizontal stretch zone of the Profile properly, only the vertical complex Wall part of it will stretch.
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