In the following, I provide step-by-step instructions to properly set up and configure the GoodRelations module for VirtueMart.
Here is my way of doing it, describing it for a fresh install of Joomla 2.5.9 and VirtueMart 2.20b, in particular starting from scratch with the default theme ("Beez2") for Joomla.
0. Install Virtuemart, assign a menu item for the shop (e.g. named as "Shop")
1. Install module ("Semantic SEO") and go to the respective module settings page
2. There, proceed as follows
a) enable the module (Status "Published")
b) select the position where to appear on the front page (in my case "position-0" using the Joomla's standard template "Beez2")... make sure there exists a template "hook" for the position you selected
c) assign the module to a menu item, select "Only on the pages selected", and check the entry for "Shop", then save your changes!
3. Head over to the front page of the shop: There you'll find the following message appear (if not, then you might change the position in the backend):
If you see this message, RDFa (structured data) is already active for your shop.
4. Turn back to the module manager (module settings for "Semantic SEO") and you'll notice that a list of configuration options became available on the right-hand side. This new configuration section allows you to further tune your structured data.
I hope this helps to overcome potential difficulties during the installation process of our module!
Best
Alex