As per the instructions on the website, I downloaded the PRO version from my account page, uploaded the plugin to my site, and it gives me an error message say that I should instead “install the free version”. The PRO version appears as version 1.4.6 on the plugins page, if that helps. There is no place to input or activate a code on the free version, and the PRO version gives that error message and nothing else.
Nevermind, I figured it out but do you really have to use both the free and PRO plugins at the same time in order for it to work? When I try to deactivate the free version after adding the license to PRO, it still says I need the free version.
Yes you are right. To make it work you need to have both versions activated (free and pro). Free version contains all base features, whereas pro version has only additional (pro) features. So pro version can’t work without free.