Go to the Billing screen and Click Actions -> Import.
Select the file that you want to import from the "Type" drop down. These files all come from either MBS or the data warehouse. Your choices are:
INVCFLAT
Paws Utilization Claims Detail
Error Detail
Denied Claims
Click on the "Choose File" button and select the file.
Click the "Start Import" button.
That's it! The next screen you see will show you feedback about the import, including with lines were successfully imported and any issues that may have occurred.