I don't know if it is just me but I am really getting confused when it comes to updating my paid add on. This is cause by all the different way developers distribute their add ons. I don't actually really know how this can be fixed other than having them downloadable from here as the free ones are. Or even a standard link to the developers method of downloading their add on. I am sure that some type of process could be added to the resource manager to handle this.