I'm using Joomla 2.5.14 with VM2 and a few weeks ago I've installed Advanced Shipping by rules plugin (http://www.open-tools.net/virtuemart-2-extensions/vm2-advanced-shipping-by-rules-plugin.html).
I've already put the rules for TNT Express but they only appear when the cart is empty. I have rules limite by weight but I can see through debug messages that the weight it's inside the expected ranges and that the rules that I'm expected to pass are validated, but when I put one product these shipping modules disappear.
Does any of you knows something about this?
For support see http://forum.virtuemart.net/index.php?topic=112127.msg377047#msg377047
Thanks jenkinhill, I didn't know that