Viewing pages such as login page is possible in author mode by configuring the page path in org.apache.sling.engine.impl.auth.SlingAuthenticator for any Resource you want to access without authentication.example sling.auth.requirements="[+/,-/libs/granite/core/content/login

set your workflow to only replicate page to a particular publisher based on configuring the agent Id's http://docs.adobe.com/docs/en/aem/6-0/develop/ref/javadoc/com/day/cq/replication/Replicator.html#replicate%28javax.jcr.Session,%20com.day.cq.replication.ReplicationActionType,%20java.lang.String,%2...

you can use a regex pattern in path field of the launcher. use can do the content modeling such that all of those paths can be combined to a single regex expression./content/usergenerated/site/blogs(/.*) 

You should set up replication agents to publish the content from author to publisher. (By default of the default agent is configured for your publisher instance running on port 4503) Please refer the documentation.http://docs.adobe.com/docs/en/cq/current/deploying/replication.html#Replication%20Agen...

Please check if you are using correct API to access the session. The OOTB code still uses old com.day.cq.workflow.WorkflowSession; codewhile the example recommend using  com.adobe.granite.workflow.WorkflowSession;http://docs.adobe.com/docs/en/cq/5-3/javadoc/com/day/cq/workflow/WorkflowSession.html