@jennym
Make sure you download the latest version of the plus plugin that goes with the latest version of the theme.
When you purchase the plus plugin, you get login credentials to the Plus site where you can always go back and download the latest version.
You go there http://shop.weavertheme.com/
Login using your credentials
Go to Your Accounts > Purchase History
There you can click View Details and download
There at the bottom you can re download the latest version