You might have to wait little more time to get support for 3.0.4 [1].    If you have tight project lines please engage with support through daycare to get the attention.[1]  http://docs.adobe.com/docs/en/aem/6-1/deploy/technical-requirements.html

Yes client context is not server side implementation & executes at client side. There is no out of the box java api available. You can use application server for session management Or need custom development by making use ResourceProvider.

You need to use mongo & with tarmk not available.  http://docs.adobe.com/docs/en/aem/6-0/deploy/recommended-deploys.htmlhttp://www.citytechinc.com/us/en/blog/2015/05/aem-6-x-mongo-backed-clustered-author-setup.html

http://felix.apache.org/documentation/subprojects/apache-felix-config-admin.htmlhttps://osgi.org/javadoc/r4v42/org/osgi/service/cm/ConfigurationAdmin.html

https://helpx.adobe.com/experience-manager/kb/ComponentDiv.html

Login at [1]. Then go to developer mode[2] and execute the script. [1]   http://host:port/libs/granite/core/content/login.html[2]   http://host:port/editor.html/<pagepath>.html    Ex:-  http://localhost:4503/editor.html/content/geometrixx-outdoors/en.html

https://docs.adobe.com/docs/en/cq/5-6-1/developing/mobile.html

Using jmx find out what query is getting executed. 

Seems like you are missing some mapping.  What i suggest is create a campaign & segment (since in you sample using oob segment might not required to create), then for experience everything just make use of authoring so that mapping will be right.  Watch the demp i gave for other threads at [1] where...

there were 2 version of install hook and was causing some installation issue.  Right way is to use jackrabbit API for hooks.    Can you please file support request mentioning-   AEM version-    Exact log files.-    Sample package and steps to reproduce the issue.