Well, I have a redirect rule in DNS configuration (CNAME record) that sends every request made to [MYDOMAIN] to https://www.[MYDOMAIN] since the second points to the actual server in AWS. In normal conditions I have not been able to activate SSL in the store without getting the redirect error.
In order to make a test and avoid redirect I commented this line temporarily in HttpsRequirementAttribute.cs
//RedirectRequest(filterContext, _storeContext.CurrentStore.SslEnabled);
After this I was able to check SSL for the store, but I am still getting errors with the plugin.
Now after I enter my credentials and hit the LOGIN button a Facebook page shows this message:
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Facebook found that Mercadone does not use a secure connection to transfer information.
Until Mercadone has updated its security settings, you will not be able to use Facebook to log in.
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My site is https://www.mercadone.co.
Also I tried again with Google oauth but then I get the "Correlation failed." error message.