Yes, that's where the API Key, Secret Key, and App Key can usually be found. However, Facebook is updating their developer area, and if you're seeing the API key, it actually means you're on the 'old' version.
In the 'new' version, slowing rolling out to all users, the API is missing. In the next release (version 4.0), we're removing the input for the API key, but until then, we still require something in that field.. so if someone reads this and is using the 'new' developer area, please put the App ID into the API Key and App Id fields in JFBConnect.
Thanks for your feedback and information about your experience!