Can I still install fee-based add-ons even when the license support has expired?

The heading summarises my question. Thank you in advance for an answer.

With the one-time purchase of a license you will receive a perpetual license for the software, as well as license support from the manufacturer for one year, which allows you to send support requests and update the software. After this initial support period has ended, you have the option of extending the support. The renewal is optional.

Just let us know, if you have further questions.