WORKAROUND:
1. Turn off Windows User Account Control (UAC) and restart the machine.
2. Uninstall Migrator for Notes to SharePoint and restart the machine again. Make sure the account you login as is part of the Local Administrator group on the machine.
3. After the restart, make sure the Lotus Notes client is installed correctly. During the Lotus Notes client setup, choose "only for the user" option, Not everyone. Make sure to run the Lotus Notes client at least once.
4. Install Migrator for Notes to SharePoint again. It should prompt for the configuration wizard now.