Hi Tam,
Thanks for your response. I followed the Step 1 -> Step 4 in the "Quick Start" and also the filled the dialog boxes following your screenshoot. However, when I select the 'cal_params.cal' file, the window was suddenly closed. I'm happy if you would like to meet online to resolve it, or probably if you have sample data, please send it to me and I will try to run the RSWAT with your sample data beforehand.
Thanks again,
Andry