Unable to build basement on Potters Splay

@PastelSpoonie 

Ok, judging from your pictures, you're trying to use the basement tools while building on a basement level.  While you would think that should work, those tools don't work that way.  To use those tools, they are used on the floor above, not on the basement level.  What those tools do is allow you to trace the outline of the floor above so you can get the same footprint on the basement level.  You need to use the regular wall tools if building on the basement level itself.

Hope this helps.