This Exception thrown when no Item exists at the specified path or when the specified path implies intermediary Nodes that do not exist.As per the log it looks like it is warning not an error, /etc/tags/properties/rep:policy node defines permissions for tag administrators.Please read this for user a...

Link is up, Have you tried recently? If so what errors are you getting.https://repo.adobe.com/nexus/content/groups/public/org/apache/maven/plugins/maven-metadata.xml 

Here is the article from adobe on changing the login screenhttp://helpx.adobe.com/experience-manager/kb/CQ5HowToCustomizeTheLoginScreen.html

There could be couple of reasons for  handshake failure:Unsupported or Incompatible cipher suites in use by the client and the server.Incompatible versions of SSL in use (the server might accept only TLS v1, while the client is capable of only using SSL v3). Again, the client might have to ensure th...

I believe there could be some typo when you followed the tutorial. I suggest to download the zip package to your desktop, extract it and compare your files with package. 

Have you tried Tar optimization?Follow this guide to do performance tuninghttps://docs.google.com/document/d/1qoBGtxU1UlWjyRiINIifPAzHU8-C-HjK2lBYsmg-Cbc/edit

Have you created namespace? where do you see this issue.Please look at the following article for creating namespacehttp://cq5cms.blogspot.com/2013/02/creating-custom-namespaces.html

It seems that you that you attempted to post to a node which doesn't exist, resulting in this exception.Have you checked whether the node exists in crxde?

It seems that you are using JcrUtil to copy a node. Node copy just copies a node not a page. I believe you need to use PageManager API to copy page.

Have you tried CQ5 builtin profiler? Try these linkshttp://helpx.adobe.com/experience-manager/kb/AnalyzeUsingBuiltInProfiler.htmlhttp://cq-ops.tumblr.com/post/14171314444/how-to-use-cqs-own-built-in-java-profiler