Trouble with Google Apps Custom Domain SSL
Solution 1:
This was answered by a friendly member of the community and then immediately deleted (not sure why...) but not before I spotted his answer and used it, to great effect :)
openssl rsa -in privateKey.key -text > private.pem
openssl x509 -inform PEM -in www_mydomain_com.crt > public.pem
The above two commands produce private.pem and public.pem, which are accepted fine by Google Apps dashboard.
Thankyou!