Here is what i do:
create a new test suite with let’s say 4 test cases
create a new test run, select the previously created sutie as input
-> test run contains of 4 test cases
update the created test suite and add lets’s say another 4 test cases (im my case I import them via csv)
-> the test run now contains 8 test cases (as I have selected to add all test cases from the suite) BUT the pie chart still shows only 4 test cases. this is until the one of test cases gets a status update - the pie chart then gets updated to.