I am reporting on my experience installing and using Middleman for the first time. My system runs OS X.
As is almost always the case with open source software, the process had some bumps.
The command listed on the web site “gem install middlemen” fails on my system because I do not have write access to the /Library/Ruby/Gems/2.0.0 directory. I got past this problem using sudo.
There were other errors reported whose significance is not obvious. These were all of the form:
unable to convert “\x89” from ASCII-8BIT to UTF-8 for lib/middleman-core/meta_pages/assets/glyphicons-halflings.png, skipping
The instructions say to install Xcode (it was already installed), but do not specifically say to install the command line tools. Thus, my attempt to create a project failed. The error message explained what to do, and after installing the command line tools, I was able to create the project.
Compared to other open source projects, my experience was pretty good, but there is room for improvement.