Hi!
Reading Visvanath Ratnaweera's deep dive (https://moodle.org/mod/forum/discuss.php?d=378935), it helped me to point what was wrong in my configuration: in my Moodle auth_ldap configuration, memberattribute was empty. I set it to "member" and now cohorts are created in populated correctly.
Now I want to have the "displayName" attribute of the groupe to be used instead of the name (CN).
The plugin dot now allow to change this unfortunately.
Looking into the code, it looks like the name of the group is specified on line 163 in localib.php:
array_push($fresult, ($groups[$i][$this->config->group_attribute][0]));
How to replace "groupe_attribute", that is CN, with the "displayName" attribute?