Just beneath the main preview window, there is some red text and warning me about my ICC Profile. What does it mean?
When the text is red, it means there is a mismatch between the destination profile indicated in your Process tool and the Proof Profile. The Proof Profile is the ICC profile the Capture One is using to display the preview image in the main preview window.
To view your current Proof Profile, go to the Image menu and select Proof Profile. A fly-out window with a list of ICC profiles appears. The profile with a checkmark next to it is the ICC profile that Capture One is displaying the main preview in. When they match, the text is black and no alert icon appears. If they don't match, the text is red with an alert icon next to it.
If you are processing one file to multiple ICC destinations, then the alert box remains black if any destination matches the current Proof Profile.
For your convenience, you can place the Proof Profile tool in the Application window. Go the View menu, choose Customize Toolbar, find the Proof Profile tool, and drag to anywhere in the toolbar.