ACS Commons mail service simply uses the OOTB AEM Day CQ Mail Service (it just calls that after composing the email from a template) - so in terms of what mail service ACS Commons Email Service can integrate, is wholly dependent on what OOTB AEM Day CQ Mail service can integrate with.

admin/admin doesnt work on Cloud Service environments.  You need to make a local account in your AEM as a Cloud Service author env under Tools > Security > Users  and make sure it's permissioned to write to the specified assets folder.  

This is because you are trying to use the tool to upload to a local quickstart-based AEM (the AEM SDK presumably). This tool must be run against a true AEM as a Cloud Service environment (that runs in the Adobe Cloud). 

Can you provide exactly how you are invoking it?

> Use case 1:- In dev , do we need to give the template authors access only to developers .What about in QA - is it only to QA folks? Subsequently in stage & prod(only for business authors) ? It depends. If developers need to create/modify/delete templates in Dev to do their smoke-testing/cyclone-te...

Be careful about overlaying the OOTB headlibs.html and friends - there is a reason why Core Components Page has already seeded the implementation with "customheaderlibs.html" .. its because that's where you should put yours so you're not overlaying the provided one. If you overlay the provided HTML,...

Since these are included via the ClientLibrary Manager in AEM you can't manipulate the HTML tag used.You could write a Sling Pipeline Transformer to add a new attribute to the tag tho, similar to [1].  [1] https://github.com/Adobe-Consulting-Services/acs-aem-commons/blob/master/bundle/src/main/java/...

If you are able to download the original rendition and open it (showing there is nothing wrong with streaming the bits off the original rendition JCR node) then im not sure ... Since you can update other Tiff's it sounds like there is something weird w/ this Tif's manifestation in AEM. You could try...

ah - youre right. sorry about that - maybe that code is actually buried in the cq/Page impl. I dont see anything in the Core Components project that looks like it performs that actual redirect itself.

Can you try downloading the misbehaving tif's original rendition?