Please beware, any PPC product will be available to purchase by any one without a password should the "Buy Now" button be visible.

The "Buy Now" button appears in "All Products" "New Products" ect... I don't think you really want client images appearing in these sections anyway.

The best way around this is to add attributes to your product, then the "Product Details" button shows, when clicked it will ask for the password.

I am not a coder. I had someone from the forum write this for me and I uploaded it for people to use. Sorry, I dont support this thread as I am not a coder, for then I have no idea how to fix things.

Maybe someone whom knows how to code can add that feature in there, but in the meantime, your best bet is to add attributes to your products as stated above :)