Unable to inset on ends, but sides OK

 From:  Frenchy Pilou (PILOU)
12098.7 In reply to 12098.6 
https://moi3d.com/4.0/docs/moi_command_reference10.htm#shrinktrimmedsrf

and some relation with : Q: Why does show points work for some objects but not others?
https://moi3d.com/wiki/FAQ