I forgot in the response above to post the whole error message I get.
On the macOS Sierra I get this message (posted below, I report the step at which it gets stuck).
======================================================
STEP 5 (out of 6): SOLVING THE MODEL...
======================================================
setting up boundary conditions...
Info : Running 'lib/getdp-3.2.0/bin/getdpMac example/
nyhead_parietal_setting.pro -solve EleSta_v -msh example/nyhead_parietal_setting_ready.msh -pos Map' [GetDP 3.2.0, 1 node, max. 1 thread]
Info : Started (Thu Jul 22 12:35:19 2021, Wall = 0.207394s, CPU = 0.104169s, Mem = 4.98438Mb)
Info : Initializing Gmsh
[1m [31mError : Unknown number option 'Mesh.ChacoHypercubeDim' [0m
[1m [31mError : Unknown number option 'Mesh.ChacoMeshDim1' [0m
Info : Selected Resolution 'EleSta_v'
Info : Loading Geometric data 'example/nyhead_parietal_setting_ready.msh'
Info : System 'Sys_Ele' : Real
[34mP r e - P r o c e s s i n g . . . [0m
Info : Treatment Formulation 'Electrostatics_v'
0% : Pre-processing
10% : Pre-processing
20% : Pre-processing
30% : Pre-processing
40% : Pre-processing
50% : Pre-processing
60% : Pre-processing
70% : Pre-processing
80% : Pre-processing
90% : Pre-processing
Info : System 1/1: 2339107 Dofs
Info : (Wall = 51.7185s, CPU = 46.6292s, Mem = 1540.71Mb)
[34mE n d P r e - P r o c e s s i n g [0m
[34mP r o c e s s i n g . . . [0m
Info : Generate[Sys_Ele]
0% : Processing (Generate)
10% : Processing (Generate)
20% : Processing (Generate)
30% : Processing (Generate)
40% : Processing (Generate)
50% : Processing (Generate)
60% : Processing (Generate)
70% : Processing (Generate)
80% : Processing (Generate)
90% : Processing (Generate)
Info : Solve[Sys_Ele]
Info : N: 2339107 - preonly lu mumps
lib/getdp-3.2.0/bin/getdpMac "example/
nyhead_parietal_setting.pro" -solve EleSta_v -msh "example/nyhead_parietal_setting_ready.msh" -pos Map: Killed