I want to outline what I think these two programs do as in my understand and someone might be able to explain where I have it wrong.
Responsive site designer works on absolute positioning, therefore pages are created at set breakpoints like 320px 768 px and 1024 px etc etc.There fore if a viewer has a screen say 400 px under the responsive site designer he would see the 320 px version with more white space around the edges.
Responsive layout maker is fluid in design. In the example above (re 400px) using responsive layout maker you could design it such that the person using the 400 px screen would have a better experience ( visual) as the screen view would have less white space?
So therefore if you want to make a site responsive u would use responsive site designer. if you want to make the site fluid you would use responsive layout maker and html editor or responsive site designer to upload it?

Thanks. hope my rambling makes sense.

Hi Angelo, Actually both programs work the same way and make fluid frame work websites. RLM is pretty much just the frame work and background colors where RSD can do that plus be used to add all of your content from within the app. You might wonder why have both. It may not be necessary for some but RLM is handy if you want to make quick mock ups of websites for clients without all the distractions of the extra fluff that RSD has. It's also great for those users that may be using a great HTML editor like CC's HTML Editor and they want to rid themselves of hand coding the responsive frame work so they can focus on delivering great content. RSD is great for the non coder that not only needs the responsive website but needs an easy to use app to add all the needed content to their pages.