AJAX Register

When installed AJAX register I get the following.

        * It was not possible to copy the selected file.
        * JInstaller::install: Failed to copy file: /var/www/vhosts/pilotjourney.com/httpdocs/pjtmp/install_49ea62c95e67a/site/language/en-GB.com_ajaxregister.ini to /var/www/vhosts/pilotjourney.com/httpdocs/language/en-GB/en-GB.com_ajaxregister.ini

        * It was not possible to copy the selected file.
        * JInstaller::install: Failed to copy file: /var/www/vhosts/pilotjourney.com/httpdocs/pjtmp/install_49ea62c95e67a/admin/language/en-GB.com_ajaxregister.ini to /var/www/vhosts/pilotjourney.com/httpdocs/administrator/language/en-GB/en-GB.com_ajaxregister.ini


As a result some of the images and messages do not display correctly

Then you have a problem with permissions in your language directories.
If you're not using FTP layer make sure they are CHMOD 777:
/var/www/vhosts/pilotjourney.com/httpdocs/language/en-GB/
/var/www/vhosts/pilotjourney.com/httpdocs/administrator/language/en-GB/

So can I just ftp certain files to that destination now or should I uninstall and then install again.?

You can just install on top of the old installation after you CHMOD those directories.