Hi everyone
Some weeks ago I could resolve these issues.
The first case, which the administrator user couldn’t see all the menu’s items in the administrator’s dashboard, that was because this user doesn’t have the journal’s gestor rol .
The second issue which is about no loading the users list, that was because in the values that limit the number of items and links per page were established to 0.
Well because my administrator user doesn’t have the journal’s gestor rol I couldn’t modify the values of items and links per page different to zero using the administrator user, well I have to request to the chief editor of the journal other user with that rol. Once I had the user with the right privileges then I changed that values different to zero. This disappeared the Division by zero error and I take advantage to add to the administrator user the journal’s gestor rol and when I reload the page, I could see the missing items for the menu of administrator.
Well that was my solution I hope this could help others with the same issues.