Here are the activation instructions from “Anna V”, copy&pasted from the Skylum Community:
Once you install the app, it is automatically launched in the trial mode. The activation is possible after the second launch of the app.
Please follow the steps:
1. Launch Luminar 3.
2. Fill in your email to activate the trial.
3. After that, please click File in the top bar menu > Close.
4. Luminar 3 will be closed. Re-open the app after that(double-click on the icon of Luminar 3 in your Applications folder).
After the second launch of the app, you are supposed to be prompted to activate the app.
Here is the instruction on how to activate Luminar 3:
1. Launch Luminar 3.
2. Click “Activate” on the welcome screen and enter your email + activation code, then click the “Activate” button.