Hi,
the problem is that you are on a very old environment, Joomla 1.5, old PHP and PHP directives.
First of all you have to turn off PHP Magic Quotes, otherwise when you save a data source all parameters will be broken and no links will be fetched.
The "virtuemat/component" is a Virtuemart routing issue, it means that the Virtuemart router can't resolve to any menu item, this was probably still to an early stage in Joomla 1.5
You can set the Virtuemart Shop menu item using the parameter in the data source (screenshot attached)
Best regards
