How that preview is accomplished - that is a different store. I would
expect that it shouldn't depend on the ecommerce store at all but
rather a template used to create the catalog/category totally
independent of the store.
I remember an old discussion where we agreed on copying some of the
product screens from ecommerce to order manager. I think the same should
be done here too ie a separate template for product preview in catalog
application.
I also like Bruno's idea about merging menus. It would be a nice
addition to product preview screen.
Bilgin