Do not pay for the Pro version

I bought the Pro version for two features. One of them (site-wide galleries) has never worked, despite many, many support emails. Now I am getting an error message. Their forums say the latest version fixes this error. However, I can’t get the latest version, because in the last version they decided to force the application of a license key THAT DOES NOT WORK in order to get upgrades. So basically I paid for something that I can’t upgrade because their license key upgrade process is broken, and I have a page throwing errors because I can’t upgrade.