Calendar changed not effect to Original Duration and Lag duration

I want to focus on Lag duration, because it will follow predecessor activities Calendar, and when predecessor activities change Calendar, it will change also, i dont know how to keep it as original Lag duration...

go to enterprise 

calendars and create a new calendar

now go to activities add a column for calendar (its under general)

click in the calendar column change the first one in that column to the new calendar that you just added.

now hold the shift key and click on the last activity and make sure all activirtes are highlighted 

right click and select fill down

press f9 and rescheduel the project

go to the projects directory and make sure that your project is highlighted

click on the defaults tab and on the right select the new calendar that you just added 

now when you add a new activity it will ue the newly created calendar.

the duration of the lag does not change unless YOU change it.