Error installation Invest on Mac

Dear all
I’m trying to install Invest on Mac OS 13.31 but I got the following error message. Any help would be greatly appreciated.

Hello @Reuben and welcome to the forums!

This error is expected and one of the ways that Apple makes it difficult for everyone if we don’t distribute through the App Store. Could you follow the instructions (especially the right-clicking and context menu steps) from Getting Started — InVEST documentation and let us know how that goes?