Using more than 5 Languages???

I’m not sure if this is a version issue or not. I’ve selected the upgrade to Full Free Version in the settings, but when I go back to Languages and select additional and then hit save, they don’t save. It seems I can’t select more than 5 at a time. Is there something I’m missing? Happy to pay for an upgrade, but don’t see where/how?

https://ww.wp.xz.cn/plugins/transposh-translation-filter-for-wordpress/