I’m phone only for a while so someone else will need to check your model.
Keep the raw geometry (lines, arcs, faces) Untagged. Use Tags for Groups/Components.
Learn the basics: https://learn.sketchup.com/track/sketchup-fundamentals-part-1
Thanks for taking the time to provide explanation and answer to the problem, also appreciate you posting the learning link, exactly what i need,
By having the floor on a separate group i cant make the walls a solid group, is that because the base is not joined at the base ?
Are redrawing on one edge to re establish a face ?