CSV Generator Tools Issues

I can not seem to make CSV Generator to work.

From the directions in the help index, I select the AD object type from the list, then browse and select the CSV file from the File Name field. After I click on Generate I receive the error:

"Invalid Format: Provide sAMAccountName as header"

I exit out of CSV Generator, add "sAMAccountName" in the first row of the CSV, and retry. I receive the same error.

When I try the other options, such as "Advanced", and pick from the other attributes it does not change any of the columns.

I have tried uninstalling ADManager Plus Free Tools and reinstalling it
Running the install and application as administrator
Installing in a different location (default location installs to the created directory in "C:\ManageEngine\ADManager Plus Free Tools")
Executing CSVGenerator.exe directly (outside of FreeTools.exe)
Running in Compatibility mode as an administrator

I can not get it to work.

Is there anyone who knows what's wrong or who can help me get it working? All help is appreciated.

Thank you.