The uninstall feature of the discontinued Ignite Express software no longer works on Mac systems. You can uninstall the plugins by following these steps:
1. Open the Terminal application
2. Copy the following, exactly as typed, and paste it into Terminal:
sudo /Applications/Ignite\ Express\ 2017.app/Contents/Resources/Uninstall.sh
3. Hit Return
4. You will then be prompted for your password. When you type the password in, there will be no indication that you are typing. This is normal. Proceed to type the complete password, then press Return.
This will completely remove the plugins from your system. You can then close Terminal and you will be all set.