If I try to remote log in via HTTPS wherever I am the explorer I am using reports non secure access and forces me to chose a non secure access.
Please can I kind person tell me how to load an SSL certificate into the router.

you need to purchase a ssl certificate from a certificate authority

Thanks for the info. How do I then add the ssl to the router?
Also, how do I obtain / purchase one from?

google for cheap ssl certificate. there's loads. choose one.

on the router, you should generate a "certificate request". This will create an X509 request that should start "

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BEGIN CERTIFICATE REQUEST

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" followed by lots of ascii text. then visit your chosen certificate provider and apply for a certificate. Import the generated certificate back into your router using the "Certificate Management >> Trusted CA Certificate" page, that should then generate the certificate on your router.