When launching the workbench on OS X, MITK complains that it could not load the vigra libs. Most likely the install name is not set correctly, which is necessary on Mac systems.
Also if you try to use the cmdline plugin the miniapps fail to load because the first output when calling "miniapp --xml" is something like "could not load virga lib xyz, image not found" but the starting tag of a CTK cli is expected (<executable>)