Posted by @glennw  in my Other thread .....with one change for X10 make sure Generate between Platforms is OFF on the Structure Tab 1st.   You can do the fascia mount railing with 1 wall definition. No invisible walls needed. Define your railing wall definition with an additional external layer with Opening (no Material).  This will offset the whole rail by the wall layer thickness. Check Generate on Low Platform (Rail Style...Build From...)  Conver