phpVMS version 7 is still in development and it's advised not to use it in a production/live site.
Install phpVMS version 2 - https://github.com/nabeelio/phpvms_v2 -- OR -- phpVMS version 5.5.2 - https://github.com/DavidJClark/phpvms_5.5.x
Either can be uploaded to your site using FileZilla or another FTP client.