Use the 'Dialog Participation Step' and get the input from the user and continue accordingly. refer [1][1] https://docs.adobe.com/docs/en/cq/5-6-1/workflows/wf-ref.html#Dialog Participant Step

you can use UserManager API (https://docs.adobe.com/docs/en/aem/6-0/develop/ref/javadoc/org/apache/jackrabbit/api/security/user/UserManager.html) or use the cURL command. Refer [1][1] http://www.wemblog.com/2012/03/how-to-do-user-management-using-post.html

Refer [1] for workflow purging[1] https://helpx.adobe.com/experience-manager/kb/howtopurgewf.html

These are the standard renditions that gets created OOB, you can change according to your usecase

It should be taken care in your CSS making image as background and text as center aligned for that div

I dont think there are any integration done between AEM and backbase.One need to do a feasibility study and depends on how Backbase exposes its services for personalization. You can raise a ticket for the same and see if Adobe has anything for this.

In Eclipse,Click on File -> Import -> Maven -> Existing Maven ProjectSelect your project and click finish. It should import the existing project into your eclipse

If its not working on one version, please raise a ticket for the same

You can refer this [1][1] http://docs.adobe.com/docs/en/cq/5-6-1/developing/components.html?_sm_au_=i2HPD1LP66nRFNvM#cq:actions

once you add the cq:editconfig, you can add the property called 'cq:actions' and give the options like 'edit, delete, insert' based on the actions you need.