We have an application written in C and C++ that runs on Windows, Linux, and Mac. Recently a customer trying to install it on macOS Monterey received a message saying "cannot be opened because it is from an unidentified developer". To deal with this my company has joined the Apple Developer Program. So my question is how do we make use of that membership to get past this problem? Of the three platforms mentioned above, Mac accounts for the fewest customers, so we're not Mac experts. The software is built using Xcode but with makefiles that directly invoke clang or clang++. The finished product is packaged into a .dmg file. Note that we're not intending to put this software into the App Store.

We create a .dmg file for one of our products that tries to create a directory hierarchy under the user's (i.e., the person running the .dmg file) home directory. The packaging is done using a distribution XML file that includes this line: <domains enable_currentUserHome="true"/> We previously built the product on macOS v10.10 (Yosemite), and this approach worked. We recently switched to a newer machine that runs macOS v10.15 (Catalina). When we build the product on this machine, the installer that's produced gives a "This package is incompatible with this version of macOS" error. However, if the top-level directory that the installer is trying to create in the home directory is there, even if it's empty, then the installer has no problems. So it appears that what the installer can't do is create this top-level directory, but it doesn't have problems copying sub-directories into it if it's already there. Is there a way to get the installer to succeed even if this top-level directory doesn't exist?