trouble installing CGAL ipelets

Hello, 

I'm trying to install CGAL ipelets on my Mac (Mac OS 10.10.5)
My CGAL version is 4.6.1, Ipe version is  7.1.8

I basically followed the instructions from 
https://3d.bk.tudelft.nl/hledoux/blog/ipe-cgal-ipelets/

and the ipelets appear in the menu, but trying to launch them gives an error: 

Lua error

Data may have been corrupted.
Save your file!

/Users/lenka/.ipe/ipelets/libCGAL_minkowski.lua:15: Error loading Ipelet: 
dlopen(/Users/lenka/.ipe/ipelets/libCGAL_minkowski.dylib, 2): image not found
stack traceback:
[C]: in function 'assert'
/Users/lenka/.ipe/ipelets/libCGAL_minkowski.lua:15: in function 'run'
/usr/local/share/ipe/7.1.8/lua/actions.lua:599: in function 'action_ipelet'
/usr/local/share/ipe/7.1.8/lua/actions.lua:83: in function 'paction'
/usr/local/share/ipe/7.1.8/lua/actions.lua:37: in function 
</usr/local/share/ipe/7.1.8/lua/actions.lua:37>
[C]: in function 'xpcall'
/usr/local/share/ipe/7.1.8/lua/actions.lua:37: in function 
</usr/local/share/ipe/7.1.8/lua/actions.lua:36>
[C]: in function 'mainloop'
/usr/local/share/ipe/7.1.8/lua/main.lua:451: in main chunk
[C]: in function 'require'
 [string "require "main""]:1: in main chunk

Somehow there is no .dylib file in /Users/lenka/.ipe/ipelets/, nor elsewhere. 
Could you please suggest what should I do? 
Is it true that I need to use Ipe 6?

Thanks, 
Elena