This tool is awesome! I have used Shoebox in the past for doing this, but it was more of a process to find, download, and use that program. This is so quick and easy- the way it should be. 

The only question I have is that when I export, it tries to save the file twice. Is there a reason for that? It hasn't stopped me from using it, but it only actually saves the texture if I save both prompts, otherwise it saves an empty file.