Dear Alfonso, 

Thank you for your answer. 
I ran the command line you suggested, and it gives an error message. 


Error using conn_process (line 4266)
Non-existing source ROI first-level data for Schaefer200_yeo17.cluster001 subject 1. Please repeat first-level analyses


The message above is the one I got after running conn_process(15). 
Again, briefly explain what I have done so far: ran first-level analysis ROI-to-ROI only with schaefer 200 yeo17 and it give an error message that I posted yesterday. 

Best, 
YaeJi Kim