Hi NIMAN.
So the lines need to be enabled in the parallel projection mode. Ordinarily this is done under "3D Menu > Pan 3D View Settings", and then set Outline to true. In my Linux system I'm getting an exception currently, so this may or may not work for you on Windows.
If that fails you can manually edit the config file for the Pan3D plugin. It'll be AppData\Roaming\eTeks\Sweet Home 3D\pan3dview.xml
Edit it so the outline key is true, i.e.
<entry key="outline">true</entry>(You might want to change the outlineThickness here too.)
That should fix your issue.
Yes, I keep meaning to continue that series of videos, but I got lazy, and blocked. I've finally managed to get the hierarchical import feature added to Blender , so the structured import now works like a dream, and I don't have to explain applying patches to everyone.
There is still an outstanding issue with the stage setup that causes Blender to segmentation fault. I have a "dumb" fix that works for me, but probably causes mayhem in many other cases, and requires building Blender from source. I'm waiting on someone knowledgeable to fix this still - I definitely am not knowledgeable enough to fix this myself. (I'm doing my best give a push without becoming an annoying dick, but it has now been three releases of Blender... <sigh>)
Lastly, I need to revisit my SweetHome3D object export patch. Asking people to build SH3D is equally as bad as asking them to build Blender, so I really need to sit down and see if I can turn it into a plugin. I did post is as a patch to Sourceforge but either Emmanuel never saw it, or didn't like it. So I have to try and turn this from a crude hacky patch into a crude hacky plugin.
I should note that I'm pretty good with Python, but I suck at Java (SweetHome3D) and C++ (Blender). This is my lame excuse for not getting on with this.