Alan’s post up near the top about Section Tools is what I would now echo.
I’ve gone back to it. I find Section Tools awkward, but it’s the only efficient reliable way to create fills, and as far as I can tell it’s the only way to do it on some open polysurfaces.
But I’m only using it to create the fills, and using clipping planes* for clipping sections. That’s because though the st fills appear in the model in any view, the st section can only be set to clip in one view (as far as I can tell) which means clipping planes are required for every other view. This means creating a clipping plane plus a Section Tool section for every section view (except one).
It’s cumbersome, but it’s the only reliable way to create section fills, as far as i can tell.
*that’s for 3d view viewports. For 2D views I’m using VisualArq Section/Plan Views (not make2D) because they’re updatable. To align 2d views with st fills I move the 2d views to where I’ve put “stLayouts” (the name st gives for stfills placed independently from the model in the project). I don’t move these stLayouts to the 2dviews – 2 reasons for this 1) stLayouts can’t be placed with precision when they’re generated and 2) they can never be moved (stMoveSection only moves the plane where the section intersects the model.)