Export/Import tool for OpenCart 1.5.3.x PROBLEM!!!

When trying to export I get the following:
'Warning: set_time_limit(): Cannot set time limit due to system policy in /customers/9/5/f/schlosser.co.uk/httpd.www/upload/admin/controller/tool/export.php on line 76Notice: Error: Unknown column 'cg.name' in 'field list'
Error No: 1054
SELECT ps.*, cg.name FROM `product_special` ps LEFT JOIN `customer_group` cg ON cg.customer_group_id=ps.customer_group_id ORDER BY ps.product_id, cg.name in /customers/9/5/f/schlosser.co.uk/httpd.www/upload/system/database/mysql.php on line 49'

Can anyone shed any light, i've searched the forums and found a similar post but no solution was posted.

Also, when importing I get 'Uploaded file is not a valid spreadsheet file or its values are not in the expected formats!'

Im fairly new to Opencart and the Export/Import extension so any help would be much appreciated! I have almost 2000 products that I need to add to my product list! I presume there must be a set format for the spreadsheet in order for the import tool to work properly?

Thanks in advance.

There's a very specific format required for the free import/export tool. Make an export using the tool, and use that to format your own products.

The first error is due to your webhost not allowing you to increase the time limit for the script.

For a more flexible tool that will take a CSV file checkout the CSV or Total Import PRO modules in my signature.