The license type applies to the object you are creating. The user can see it in the tool settings window.
It is also used by https://bimcomponents.com if an object is uploaded there.
I can’t give you legal advice, but I think you should have your users accept the details of your own commercial license agreement on your site before download, and probably package your code as lcf and include a license agreement there also, or a copyright notice in the source code.
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Péter Baksa
Library Platform, Software Engineer
GRAPHISOFT SE