Interaction with multicol and mdframed results in misaligned rows

Question

This works fine with TeXLive2011 and was working fine with TeXLive2012 until I recently updated the packages. So with TexLive2011, this produces:

but with an updated TeXLive2012 this yields:

Notes:

• Also there seems to be something going on with \x. Replace \Number in the MWE with \x and run with TeXLive2012 (with latest updates). Using \show\x shows that it is undefined, so not sure why there is a problem with using \x as the \foreach variable.

• There is an warning from mdframed

  Package mdframed Warning: You have only a width of 3cm on input line 15

  but not sure what it means, or what to do about it.

Code:

\documentclass{article}
\usepackage{multicol}
\usepackage{pgffor}
\usepackage{parskip}
\usepackage{multicol}
\usepackage{mdframed}
\usepackage{showframe}

\begin{document}\raggedcolumns
\begin{multicols}{6}
\foreach \Number in {1,...,14} {%
    \begin{mdframed}%
        \mbox{AB-\Number}%
    \end{mdframed}
}
\end{multicols}
\end{document}

Answer 1

With the current version of mdframed the behaviour is nearly equal. The shown distance of the older version was a bug where I didn't regard parskip at the beginning of the environment. The default behaviour of mdframed ought be skipabove=skipbelow=0pt whereby by using parskip the option was skipabove=\parskip

If you use the current version you will get the following result:

If you want extra space you can add some skip to skipabove:

\documentclass{article}
\usepackage{multicol}
\usepackage{pgffor}
\usepackage{parskip}
\usepackage{multicol}
\usepackage{mdframed}
\usepackage{showframe}

\begin{document}\raggedcolumns
\begin{multicols}{6}
\foreach \Number in {1,...,14} {%
    \begin{mdframed}[skipabove=\parskip]%
        \mbox{AB-\Number}%
    \end{mdframed}
}
\end{multicols}
\end{document}