We have an article that shows you how to work with OR SPLITS and get them working. See -- Adobe Experience Manager Help | Invoking an Adobe Experience Manager Custom 6.4 Workflow from a web page This clearly shows use of using an OR Split within AEM Workflows.

The article that i referenced Shows you how to render an image that is located in the AEM DAM in an HTL view. In this example - we also use an outer DIV tag to determine if the author selected image.In this article - a granite resource type is used in the component dialog to select the image.(Not su...

Looks like you are doing something wrong. To work with a HTL component and get all the images correctly rendering - see this HELPX article - Creating an Experience Manager 6.4 Responsive Banner Component

As stated - AEM is not a Spring MVC framework.  There are no docs from Adobe on this use case. Adobe recommends using Sling APIs - which is what AEM is built on - not Spring APIs. The Basics

Looks like you are doing it correctly - you have a servlet that you are posting to. You can then write app logic to persist the data into a database. Are you using the DataSourcePool API? 

As Gaurav suggests - in AEM 6.4 - you should look at using the Core Components over Foundation components.

Reason it's not working is because this code does not work for Event Handlers: Map<String, Object> param = new HashMap<String, Object>(); param.put(ResourceResolverFactory.SUBSERVICE, "datawrite"); ResourceResolver resolver = resolverFactory.getServiceResourceResolver(param);Session session = resol...

AEM is not a Spring-based framework. Why would you have a requirement that is based on a framework that AEM is not? AEM uses DataSourcePool API to access databases via an OSGi bundle.

Here is an older AEM Community article that uses QueryBuilder API and places the result set into an ArrayList. You can see how HTL is used to display the list: AEM QueryBuilder Sightly Example: <div data-sly-test="${properties.search}" data-sly-use.v="com.community.querybuilder.HelloService"><b>Here...

Why would you even want to use Spring MVC with AEM. AEM is based on SLING and OSGi, not Spring APIs.