I'm just gonna be blunt about it because I've written and then deleted the start of this tutorial about 67 times so far. The "Check for Updates" feature in the Silhouette Studio is basically useless. There...I said it.
If you're running Silhouette Studio and you're relying on that little feature to make sure you're running the latest version of Silhouette Studio - you're making a huge mistake. It doesn't work the large majority of the time.