FrankT said:

I'm getting frustrated - I can't get this tool to operate properly! I've imported the test and reference images, but the "build colour correction model" button doesn't light up. I think I might be doing something wrong. Can you help?

The tool expects you to correctly crop the test frame, and reference frame. You don't have to, but in that case you have to close the figure window before being able to continue.

I will make v1.2 available again, because I'm still waiting for some feedback on the LUTs I created.

Link for download: http://we.tl/CKTV8zX6cf (available till the 12th of October)