You put those two files in the suggested folder. You need to put both.
You open a QlikView document you already have or create a new one. You switch to webview and try to create a new object. You will now have an extension object of the type 'Hello World' available. Not very useful as such but as a way of showing how extensions obects are intended to work.
.png "cfz"){kind=avatar}
.png "Former Employee"){kind=icon}