On some MacOS systems, the 5.2 Imatest release has an issue where the system temporarily freezes for under 60 seconds when file dialogs are opened.
We have traced this to the new 2019a MATLAB compiler runtime and are working with MathWorks to resolve the issue.
As a partial workaround, you can enable the file selection by going to options II and selecting “use the new uipickfiles dialog. Display previous batch of files”.
Ths is corrected in future releases.
Our sincere apologies for any inconvenience that this causes you.