Hello,
I did a brand new install of 7.1.74 on El Capitan on MB Pro with AMD Radeon R9 M370X and Intel Iris Pro.
I copied Sweetlight folder on Applications and it opens fine.
When I add a new fixture it crashes unexpectedly when I hit "patch" (I tried with and without 3D viewer to diagnose interference). I rebooted, no change. I tried several fixtures, same result.
Also If I try create to a new lightshow, I enter a name like "new" and sweetlight returns that it cannot create "new/" folder. This works fine on Windows.
Thanks a lot for supporting