I've finally got the shopping addon to install in phpnuke 8 but everytime I try and add anything to the shopping cart I get a blank page with thease errors

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /home/fhlinux183/p/phoenix-rising.co.uk/user/htdocs/nuke/html/modules/roster172_b2/addons/shopping/functions_cart.php on line 82

Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/fhlinux183/p/phoenix-rising.co.uk/user/htdocs/nuke/html/modules/roster172_b2/addons/shopping/functions_cart.php on line 84

I'm running phpnuke 8 and MySQL 4.0.20-standard any ideas?