Use ConcurrentHashMap instead of HashMapat java.util.HashMap$HashIterator.nextNode(HashMap.java:1442)check https://www.javacodegeeks.com/2011/05/avoid-concurrentmodificationexception.html

Create a lucene index as mentioned in the link shared by Ravi, set 'indexNodeName' and  evaluatePathRestrictions to true - compatVersion = 2  - async = "async"  - jcr:primaryType = oak:QueryIndexDefinition  - evaluatePathRestrictions = true    // to index node names under a specific path like /conte...

check Re: JCR event listener is not working in aem 6.4

check  Re: JCR event listener is not working in aem 6.4

Tweak the source of these tools or use the generated rep:policy xmls for each folder per your requirementsPackagers other link:Migrate users, groups, and ACLs between AEM instances

The link shared by Arun is comprehensive and includes every aspectFor a fresh 6.4 install, you'd follow the same steps for standalone install. Check the Deploying AEM section @ Adobe Experience Manager Help | Deploying User Guide based on your requirements of standalone installation or app server in...

Omnisearch works from below nodes which are marked as granite:InternalArea/libs/granite/ui/content/shell/omnisearch & /libs/granite/ui/components/shell/omnisearchYou can find the code in these paths..You may check with DayCare for a solution.

I've 1.0.10 for both core components and core-extension bundle

I assume that you have installed core components  Releases · adobe/aem-core-wcm-components · GitHub Check the browser console logs/error.log for any warnings/errors

I'm also on SP4