The first thing I did was reinstall the fortran compiler, it would not compile otherwise. I have version 9.1.0 right now.
Something unusual happened in these two days, the problem fixed itself. The only thing I did is reinstall MATLAB today. But anyway, the user material is now working perfectly in FEAP 8.5, simulation runs flawlessly on the iMac Pro.
For the laptop MacBook Pro, it compiled but I used to get a segmentation fault when I tried to open the software. I removed everything and complied everything and we are now in business!
So I guess I solved all my issues, thanks for checking.
Aurelie