Hi Tam,
You should be able to add files to the wind_resource folder on your Mac as follows:
Close SAM if it is running.
Open a new Finder window.
Go to the SAM application package -- it could be in the Applications folder or somewhere else.
Control-click the application, and click Show Package Contents.
Go to the wind_resource folder.
Copy your wind resource file to the folder, and close the Finder window.
Start SAM, and go to the Wind Resource page.
Click Refresh library.
You should now see your file listed with the other wind resource files.
Best regards,
Paul.