Change Direct Query to import mode in datamart

I create a dataflow and then imported the tables in datamart. I then created a connection. I want to import all tables as import but direct query has been done by default. When I click on each table and go to properties and then advance. I see import option there but nothing happens even when if i click on it.  Any help . I tried to see if I can get the storate option when improting tables in data mart, but I did not see any option.

pls do help