I had to uninstall this app from my joomla 2.5, as by mistake when one goes to STORE >> More info .. you see some info there but one doesn't realize exactly why that info is there because is the super user for joomla whole administrator, and because I was repeatedly the message, the user is already in use, or something like that when I was at the STORE page to input some info for vendor and I really couldn't find what user what the one in use because I had just installed the virtuemart and had done nothing yet.
So I messed up the part where it says 'More Info" and change some stuff there and then I lost entrance to joomla as admin, and had to resource to find an sql and extract that part and then with phpmyadmin import that changed info for super user. Luckily I got back admin entrance, so I would think before I install this app again, it was not pretty straight when one goes to configure the store and keep saying the user is already in use and there is not default currency and it didn't matter what currency I input kept telling me the same over and over. I did tried the latest version of virtuemart 2.0.2b I believe it is.
VirtueMart is a component, not an app!!! And it does require some experience of how to use Joomla before installing and configuring, together wih a logical approach. Of course, there is documentation available to help, such as http://docs.virtuemart.net/tutorials.html or http://dev.virtuemart.net/projects/virtuemart/wiki and books in several langages, eg http://oscmanuals.com/virtuemart-user-manual-with-free-install-quick-setup-guides-p-209.html or http://tinyurl.com/a63j643