This is not the same website. But I copied that file from the location where registration.php is located. So this should be the same, I think?
I worked locally with this, so unfortunately I can not give you any FTP information. But if you want, we can skype?
I found this on the web: https://formvalidation.io/guide/validators/greater-than/. It is an extended version of the validations included in Bootstrap. However, I have not tried it yet. But the best thing would have been if we could solve it so I can still use WebAssist validation.