Does anyone know if there is any tricks to getting SFTP to work? I'm getting the same error each time, saying that the hostKey doesn't match. Have checked documentation etc, but can't seem to get it working.

usually its usage of ssh-keyscan and going through the keys returned until you find one compatible

Did you go through the process of creating the GUID required for calls to sFTP? If not, you'll need to.

Thanks @NElliott! That did it