Since you are starting with v1065 (first, don't delete your installation file for that version, just in case you want to install it), then you will want to do an uninstall first.
Just to be safe, in case the uninstall procedure doesn't work, copy any directories with your projects someplace outside of your AppGameKit installation path. So, if you need to completely delete the AppGameKit directory, you won't loose your work that way.
When upgrading between major versions, it is a very good idea to completely uninstall the previous version and make sure that all old files are removed.
EDIT: And I agree with AgentSam, I keep multiple versions around. That way I can test to see if an error that suddenly shows up was introduced in a new version or not.
Cheers,
Ancient Lady
AGK Community Tester and AppGameKit Master