I’ve discovered a better way to use wpeStore along with NextGen Gallery to sell your items on your WordPress website.
Instead of sticking the wp-estore.php file in the View folder, add a folder called nggallery inside your current active theme folder, then put the wp-estore.php file in there. Everything else mentioned in the previous instructions I mentioned remains the same.
This way whenever NextGen Gallery plugin gets updated you won’t have to do anything at all, this new way is update-proof! Gotta love that!