By default, macOS will only allow apps to run that have been installed from the App Store. To install OMN, you will need to override this, which you can do either temporarily or permanently.
1. Enter System Preferences
2. Select Security & Privacy from the top row of icons:
3. You will now have the screen below. Please click on the padlock bottom left, and when prompted input your password.
4. In the "Allow app downloaded from:" section at the bottom of the page, please select "App Store and identified developers". Anquet is classified as an identified developer as we have signing certificates issued by Apple.
You should now find that you can run up OMN on macOS.