Having trouble importing an existing cmake project into CLION

I am trying to make modifications to the open source crtmpserver project (https://github.com/shiretu/crtmpserver).  As I have not done C++ in over 15 years I would prefer to have an IDE to help me along the way.

In that repository there is a builders/cmake folder with existing CMakeList that is correctly set up.  However every attempt I have made to try and import it into clion has been an utter failure, with zero autocomplete and building always failing.

Is this even possible to do without trying to set everything up manually?