Validate that you're following the steps mentioned in this article: http://www.aemcq5tutorials.com/tutorials/create-system-user-in-aem/

I couldn't locate this exception in the source code @ acs-aem-tools/CsvAssetImporterServlet.java at master · Adobe-Consulting-Services/acs-aem-tools · GitHub Probably best bet would be to enable logs on "com.adobe.acs.tools" or debug this java codeEven there is a similar/open issue - CSV asset impor...

As a temporary solution till the time you get a patch from Support, you could set the response status 200 in 404.jsp and then the contents of 404.jsp would get served as 200 and hence get cached in dispatcher.Just make sure to evaulate the pros/cons of this approach.

Per my knowledge, a better design would be to manage the style-design options in React app itself rather than managing it in AEM via style-system

Try this - How To Prevent Authors From Deleting a Child Component | Perficient Digital

The path doesn't need to be hardcoded and instead it can be dynamic or a configuration or other ways.Per my knowledge, for this use case, Sling is behaving as it should to resolve the urls based on custom configurations. It all depends on ranking/execution of services.I would let other folks to reco...

As mentioned above in the second solution, use '/domain_com/en-us/...' as the relative url in your jsp/htl script rather than '/en_us/...', that should fix your issue. 

Yes, you can create mappings that aren't host specific. A solution would be to use Sling Resource Resolver Factory - URL Mappings in /system/console/configMgr only for inbound urls but not for outbound urlsDo you share the root path with multiple domains that controlled via sling mappings? If yes, t...

If the same content tree is mapped to multiple domains via sling mappings as in your case, it could very well lead to the issue as you have identified in resolver.For turning off external redirects, you need to fix your sling mappings to remove "sling:redirect" properties appropriately per use case....

Could you validate your credentials & network/proxy as it throws "ConnectionException"?