I cannot get the Dorico Elements 6 installer to open or do anything on my Mac. What am I missing?
Welcome to the forum @Andrew_Sargent .
Did you use the Steinberg Download Assistant to download Dorico or did you download the package directly from the Steinberg website?
In the first case, the Download Assistant should also do the installation for you. In the latter case, you unzip the downloaded file and double click on the PKG file. That shall also invoke the installation process.