[cherie]

Configurator does most of what you describe in the first point. You might want to take another look at the manual. I'm not clear on the second point as you can search for products by sku but building configurable products is very complicated and takes a while to wrap your head around.

Configurator is very complex already and what you are describing takes it to another level. A super custom configurator that includes keeping the customer all on one page. I don't know of an add-on that does this so you'll most likely need to have it custom-built. We have customized Configurator so the products appear on the step page but it was very time consuming to just do that. In your case it might be best to start from scratch using Configurator as a model. I would start very simple then add more capabilities later.