Pay type with negative effect

Hello,

I am trying to set the configuration for the leave administration management but I am stuck in the configuration of the pay type for unpaid leave of absences.

When we do this  process manually, we enter negative hours for the leave and that decreases the number of hours to be paid but when I used the leave administration functionality, the hours are entered in time entry as positive and in despite of having selected negative for effect on gross pay and on net pay, when I run pre-payroll, the hours, the gross pay and net pay are increased instead of decreased.