WebWasher is a ad filtering program that strips banner ads from web pages before your web browser even gets them. It also enhances security by blocking most popups, popunders, and scripting as well.
Webwasher install spawns a notepad.exe instance and will not continue until notepad has been closed. After notepad is closed, it will open the browser config menu. At that point, just kill it. Hence the 10 and 5 second delays in the cmd.exe install script. There is no known way to install the application completely silent.