To draw edges between 2 curves (step 5)you could paste this into some Ruby code editor. Untested.. a=Sketchup.active_model;b=a.entities;c=a.selection;d={};c.grep(Sketchup;;Edge).each{|e|if cc = e.curve;next if d.has_key?(cc);d[cc] = cc.vertices.collect{|v| v.position };end};if d.length == 2;crvpt1 = d.values[0];crvpt2 = d.values[1];unless crvpt1.length == crvpt2.length;puts "unmatching points from curves";else;gps = b.add_group.entities;for i in (0...crvpt1.length);gps.add_edges(crvpt1[i], crvpt2[i]);end;end;else;puts "Select only 2 curves, please";end Edit: Compressed it to 1 line for pasting into Ruby consol..

SketchUp is primarily a 3D modeller. As such when you draw a rectangle on the ground plane as in your example, the expectation is that you'll make that 3D and so it places the outside or front face down. The blue faces is expected to become the inside of the bottom of the 3D shape. There's nothing wrong with that.

In Pro when you Export a 3d DXF or DWG there is an options button on the dialog. This opens an options dialog in which you can specify what will be included in the exported data. One item is 'Construction Geometry' [aka Guide-lines and Guide-points] by default I think this is unchecked... Check it and they export as XLines/Rays and Points in the CAD version...

yes

There is also the Sketchup Sandbox tools to create the grid.

@unknownuser said: I'm extruding by 0.1 Maybe also don't works with tiny unity like mm Scale you model *1000 before make something then unscale *1000