There isn't a public facing open download anymore.  The download follows the AEM model and can be requested from a sales rep or partner manager.  Let them know what OS/Appserver you desire and the request can be satisfied.

There are two approaches, you can run AEM Forms JEE and the apis remain the same or you can run in a pure OSGI implementation and use the following https://helpx.adobe.com/aem-forms/6-1/javadocs/index.html.  All services with the exception of AEM Forms Workflow and AEM Forms Document Security run on...

This is confusing to me, can you open one of the protected PDFs and go to File>Properties and click the security tab and let me know what it says beside Security Method? 

I need more information, as mentioned above it would be helpful to know what you're doing to protect the document.  LiveCycle Rights Management prompts for a userid/password otherwise the server is not requesting a password it's the PDF viewer that challenges for a userid/password.  Are you using an...

Is there a specific reason you don't want to use LiveCycle Designer (xfa forms) ?

Items like var sometext is standard Javascript and there are plenty of tutorials that aren't Adobe specific.  For LiveCycle specific functions the intellisense helps and there are several blogs out there like http://blogs.adobe.com/formfeed/ that will help.

I split this into multimuple lines but you could likely do it in one if you prefervar sometext = this.rawValue;sometext = sometext.toLowerCase();this.rawValue = sometext.replace(/\b([a-z])/g, function (_, initial) {return initial.toUpperCase();});

If you have text with http://web.com then it will be interpreted as link.  If you need to do this dynamically use a floating field

It's at the top of the download page:To download the latest release of Designer, select the desired language and enter the following serial number.1139-1001-3886-4854-1284-1828