This problem did not come from templates or module you'll see. You can go to backend of Virtuemart, in products list, please choose a product to edit then save it. Repeat this action for all sample products (Just open then save) to update the new user state. You may also apply above action for categories.
After that you can see the front-end.
( The reason is when you install the demo package, the new admin user created and in some case it did not update the new user state for sample products. )