Userpro license question?

The previous webmaster of our website bought a userpro license with standard 6 months support. Almost at the same time as the support expiry, the plugin stopped working. When I try to activate the plugin, the whole web site hangs, and I have to change the name of the userpro directory from cpanel to deactivate userpro.

My question is whether userpro license is a renewable license (i.e. one needs to pay every six months or a year) or when you pay the license you have the right to use it for the rest of the time. I asked the question to the author but they asked $10 (i.e. sign up for extended support) to answer this simple question.

Your response is much appreciated.