If you encounter an error with one of the Spitfire Plugin products, it is always best to attach your log with your support ticket. This will help the team identify the issue by speeding up the troubleshooting process.
To find your log file, click on the Red Error mark, followed by the Show Log hyperlink.
This will link you directly to the file, which you should now drag and drop into your support ticket/ email.
If you do not have an error in your log, you can find the files directly in:
Mac OS: ~/Library/Logs/com.spitfireaudio