To get the details of an item to appear on a particular detail page you will need to filter the recordset for that specific product. You would normally do this with a URL parameter like the items id. You would have the recordset crafted and filtered on this value, then wherever you use the bindings for this recordset on the page it will show the details for that specific item.
The add to cart should make use of these recordset values and add them to the cart. Please describe how you have the page setup in this regard and the exact result that you are getting. Also post back with a link where I can see the issue and make sure that I have the current version of that page available. If it is in the current zip archive you have attached then just let me know.