One follow-up question:
I have followed the steps described in https://developers.maxon.net/docs/Cinema4DCPPSDK/html/page_maxonapi_dev_macos.html#page_maxonapi_dev_macos_notarization_xcodecodesigning. Created a ZIP of my plugin (using Python, but it's still a normal ZIP, with the plugin binary, res folder etc.), signed it with my certificate from apple, and uploaded it using the
xcrun altool --notarize-app ...and-so-on... call. Upload successful.
However, the plugin is never notarised, and looking into the notarisation history, it tells me:
2020-11-27 08:44:14 +0000 b1cb2d34-a374-40b4-95d3-64a5d9e4df38 invalid 2 Package Invalid
I saw posts on the web from people who had the same problem. They fixed it by enabling "Hardened Runtime" in their projects. I already did that, as described in the SDK docs, but the problem persists.
Is there any way to find out what's to invalid about the package?