Products and Category links not working

I have installed marketpress on my wordpress site. I am using 3.1.3 (latest). Upon installation of the plug and activation, it created a page called Store. When you click on Store it brings up the store navigation...but if you click on Products for instance...i get a blank post with a smiley face. If you hover the mouse over store and the dropdown menu appears and select store...same result. If you choose a selection from Browse by Category on the store navigation you get....Fatal Error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 45451 bytes) in /home/content/01/7949301/html/wp-includes/shortcodes.php on line 293

Not sure what is going on but its a nuisance. Anyone have any ideas? the website link is

Thanks in advance.