Here are the Replication Configuration docs: https://docs.adobe.com/docs/en/aem/6-2/deploy/configuring/replication.htmlIf the out of the box replication agents do not meet your requirements then write a custom one using this API: https://docs.adobe.com/docs/en/aem/6-0/develop/ref/javadoc/com/day/cq/...

Most of the use cases I have seen with this class is modifying links: https://sling.apache.org/documentation/bundles/output-rewriting-pipelines-org-apache-sling-rewriter.htmlWhat comments are you referring to? 

The Image component lets you upload content from the file system or you can drag from the DAM using the Content Finder - as shown here: For difference between DAM and MediaLib, see this doc:https://docs.adobe.com/docs/en/aem/6-1/administer/content/assets/medialibrary.htmlAlso - they are doing a GEMS...

Looks like something changed in the configuration. Please read the AEM documentation here: https://docs.adobe.com/docs/en/aem/6-1/deploy/configuring/configure-logging.htmlAlso - here is an older community thread that may help too:https://forums.adobe.com/thread/1173572

Back end is the way to go as you have much better control with Java/OSGi. Use front end to display the data. There is a sample package and article for this use case: https://helpx.adobe.com/experience-manager/using/restful-services.htmlThis will point you in the right direction. 

I am not clear in what you are looking for. Seem you want to know how to restrict a path field values where the path field is used in a multi-field control. 

I would look at using JCR SQL2 to perform this type of query: http://labs.6dglobal.com/blog/2014-10-07/9-jcr-sql-2-queries-every-aem-dev-should-know/https://wiki.magnolia-cms.com/display/WIKI/JCR+Query+Cheat+Sheet

Nice suggestions noksc. Those are the correct steps. You can see those steps in action in a real world component created by Praveen by reading the article that Scott references. 

A component is only script,  there is no  API that will reload it. You can use web APIs to reload content. For example http://www.w3schools.com/jsref/met_loc_reload.asp. 

If you want to know How To Query the AEM JCR and then display JCR data in a component (for example, a GRID in a page component) -- see this article: https://helpx.adobe.com/experience-manager/using/querying-experience-manager-data-using1.html