I installed the V3.6 in a new redmine instance. It was not possible to change the permissions as ERPMine->Settings->permissions was not enabled to my user (a redmine admin user). I downgraded to 3.5.1, and I was able to enable all permissions to a group, and put my user to this group. Then I was able to go back to 3.6, and everything seems to be working fine.
I installed the V3.6 in a new redmine instance. It was not possible to change the permissions as ERPMine->Settings->permissions was not enabled to my user (a redmine admin user). I downgraded to 3.5.1, and I was able to enable all permissions to a group, and put my user to this group. Then I was able to go back to 3.6, and everything seems to be working fine.