Hello,
I'm trying to use roboDK for a 3d printing project as well and I get the same problem but using windows. When I select an object in the 3d printing Project tab it says "Slic3r Project not found. Install Slic3r on: C:/RoboDK/Other/Slic3r/ from slic3r.org".
I did as you did I tried with version 1.2.9 and 1.3.0 but I still get the problem.
How did o solve the problem? Is it working with you now?
Thanks in advance,
João Sobral