Adobe Muse is NOT designed to be the tool you want it to be. I don't use a screwdriver to drive nails into the wall. I have tried to use Macaw and while it is interesting and somewhat fun to use, it is lacking many productivity enhancements to be a full-fledged "site" design program. Muse was created for people who are NOT web designers to build small sites for themselves and their clients. It is NOT intended to be a professional web designer's tool. It is aimed at users of Adobe InDesign. It's interface and workflow reflect the sensibilities of print designers. That being said, Muse does some really cool things, like dynamic CSS menus, audio, video and slide shows that would take you days to build properly by hand. Where are those tools in Macaw?
As far as I can see, Macaw is a one-trick pony. You get one feature but lose a dozen others. The real tool for doing complete, fully responsive sites in the Adobe family is Dreamweaver. The latest version has many tools for doing media queries and creating HTML5 and CSS3 code and styling. It also has site management functionality that is missing in Macaw. If you change the name of a file Dreamweaver will correct links to that file site wide. Will Macaw? Dreamweaver has a multithreaded FTP engine built into the program that allows you to upload and synchronize files in the background, does Macaw?
When I build a site, I have many jobs to do beside building responsive CSS. Macaw is useless for almost all the other jobs I have to do. With Dreamweaver most of those functions are built in. The latest version (CC 2014) got some major improvements and they are still working on some great new features for future releases. Muse is great at what it does. But don't expect it to do what it's not designed to do and probably never will.