Nicolas, you are the best. The site is under development, I only had one product to play with and guess what... there was no Tax Category selected.
I think I know what happened. When I was experimenting, I created a tax category, later when I created the product, I assigned that category to it. I think the problem stared when I deleted the test category and the product might have defaulted to None.
I have no evidence to support this but letter today or this weekend I'll try to repeat the steps above and see what happens with the tax category. I'll let you know.
Looking at the FAQs for taxes (
Tax Rules FAQs
), product tax category selection is the last thing suggested. I guess I didn't clue in on that.
Thanks again for your help with this.