I had recently upgraded to OSX Catalina 10.15.2, with the last version of Unity 5.6.3 and I can not get passed thru the project selection window, after the project libraries get imported Unity becomes unresponsive and there is nothing possible to do other than “Force quit”. This is very frustrating and I am looking around but I don’t find any information about it. Any help would be appreciated. thanks
Unity 5.x is incompatible with Catalina, and will not get the fixes for it, as 5.x’s support cycle ended a couple years ago. From other threads on the topic, the biggest issue is Apple’s choice in Catalina to end all support for running 32 bit applications, and some functionality of the 64 bit Unity Editor had been done in 32 bit still. The latest versions of 2017.4.x, 2018.4.x, and 2019.x are supposed to work correctly on Catalina, as any remaining 32 bit components have been moved to 64 bit.
So to use 5.x on Mac though, you’ll have to downgrade your OS. For more information, search for the main threads on the Catalina issues.