I want to install a newer version of EAC, do I have to uninstall the previous install first?

Unless otherwise indicated on a new release, for updates just extract the new exe file in your EAC dir. (I.e. overwrite the old exe) and you will retain the old settings. If you want to delete the old options nevertheless, just delete the key HKEY_CURRENT_USER\Software\AWSoftware\EAC .