I’m sorry you weren’t able to figure out the API, you may want to check out this support thread: http://ww.wp.xz.cn/support/topic/api-wont-load-1?replies=8. That information will be added to the next FAQ update.
The reason we upload “empty” videos is so that we can update the videos via Vimeo without having to update the plugin repository. The API video is now available and the tutorial will be uploaded in a day or so.
The tutorial video is now on line as well.
@limmengwei This is a pretty awesome Google Font plugin. I cannot believe that you gave it one star because you could not figure out how to create a Google API key. It seems unfair to the developer and inconsiderate to the rest of the WordPress community that rely on these reviews.
I had never created A Google API key either so I simply Googled “How to create a Google Font API key” and in less than 2 minutes I had one. It was not exactly rocket science.