Upgrading our projects so we can use them in ProBuilder isn't as simple as deleting Prototype and adding ProBuilder because of the way it is programmed; they both use different types of components. Thankfully, there is a tool that can act as a intermediate stage and that will save all of the data needed so we won't have to redo everything. So let's learn how to go about doing it.
Note
Before continuing, I do want to mention that the upgrade process is not reversible, and if an error occurs, you will almost certainly lose all your work. Make a backup of your entire project before attempting to do this!
It's also important to note if you are using ProBuilder Basic and updating to Advanced and are using 2.4.7 or higher, all you need to do is import your new package.
To be completely sure of the steps needed and what to do for whatever version of the tools you're using check out the following page: http://www.protoolsforunity3d.com/docs/probuilder/#installingAndUpgrading...