Continuing the discussion from Cannot publish website:
Answer is in my reply to your original post…
Add port number to server
i.e.: olympus.krystal.co.uk:722 for sftp
I still think your website root is incorrect, but I don’t use that host so will reserve judgement. 
Edit, if this is an add-on domain, then the root would be path: sanderson-windows.co.uk as per these instructions for best case use
HTH
Brad