Like a few other reviewers I also bought the PRO version because when I get value from a plugin I like to reward the developers.
Unfortunately in this case the developers are greedy and short-sighted.
Last week we changed the URL of our WP blog. Everything else stayed the same, we just changed the URL. The plugin showed an "Authorization Failed" error. I contacted the developer and he refused to re-activate the license.
BE WARNED!! THIS DEVELOPER WILL REFUSE TO SUPPORT YOU IF YOU EVER END UP CHANGING YOUR SITE URL!!
I'm sure the developer will respond immediately to this bad review and say something like "this policy was explained during the purchasing process." My answer is "SO WHAT?" A stupid policy is a stupid policy, regardless of whether you explain it during checkout.
Developers like this who provide poor support for their PRO versions make it less likely that people will buy PRO versions of other plugins.