You may not have a "search" requirements yourself. When we mentioned "search" it does not imply a search feature or something like that. Oftentimes AEM needs to fetch properties/nodes to assemble and render pages and for doing this a query is built and executed behind the scene . We are referring to...

On top of what Leo mentioned you should actively check the logs to see if there has been any traversal query and if there is such query just create a relevant index. You can use Oak index definition generator for this purpose.Oak Utilities : Index Definition Generator 

Check the following post:Delete Dam Asset Workflow

In addition to what Vishu mentioned also its good to check the following document:Post Upgrade Checks and Troubleshooting

I tested this in the latest service pack i.e. 6.4.5 and it seems to be working and translating the content fragments including the title. In the translation cloud service configuration make sure for content fragment translation you include everything: 

If the issue persists after reviewing the doc provided by Yanira let us know what service pack of AEM you are running ... there might be a known issue in content fragment translation that has been fixed n a later service pack of AEM.

Adding to what Leo indicated, also make sure the .dll file is accessible

Possibly "sling:resourceSuperType". This enables the component to inherit.For example a text component will inherit various attributes from the standard component.scripts (resolved by Sling)dialogsdescriptions (including thumbnail images, icons, etc)AEM Components - The Basics

Can you clarify the following:1. the same username is used when bypassing dispatcher i.e. using IP and port number2. you are able to see the full repository tree when using IP and port number

From what you said it seems that it might be blocked at dispatcher ... I don't think you need to enable it just check the dispatcher config file to ensure its not blocked. You may have an entry similar to this that block access to CRX and CRXDE Light using filter rule: /ruleLabel{/glob "* /crx*"/typ...