More or less each time. I can reproduce this error every time I'm importing bigger models. Not so often with smaller.
It would be nice if continue didn't work until it was safe to use.
Copy/Paste works only within the same Sweet Home 3D program.
Of course. I even saved the linked project with v6 and re-opened it. After copying a spotlight, the only option I get is to Paste Style – Paste is greyed out on the menu.