title: MacVim - How to properly set up vimdiff to work with SourceTree?
body: <p>I'm using MacVim as my editor and Atlassian SourceTree (v1.5.3) as my VCS frontend. I have MacVim's command line helper script <code>mvim</code> installed and <code>mvimdiff</code> properly symlinked.</p>
  
  <p>I want to use <code>mvimdiff</code> as a external diff tool for different kinds of VCS repositories (Git, Hg, SVN) in SourceTree. </p>
  
  <p>When "External diff"ing a file/merge conflict via SourceTree, both diff windows are just empty.</p>
  
  <p>Manually diffing files via <code>mvimdiff file1 file2</code> works properly.</p>
  
  <p>These are my settings in SourceTree: <a href="http://i.stack.imgur.com/2eQZD.png" rel="nofollow">http://i.stack.imgur.com/2eQZD.png</a></p>
  
  <p>How can i set up MacVim/gVim to work with SourceTree?</p>