I’m not entirely sure what the problem might be. That should be the right version of Inkscape, and the current version of Xquartz is XQuartz-2.7.3.
One thing to check is to see if there might be an older copy of either Inkscape, Xquartz, or X11 on your computer; please look in both your applications folder and in your applications/utilities folder. (If there is, it could be the case that your computer is opening one of the old versions when you just ask your computer to open up an existing file.)
Also, if you can get it open (even for a moment) click and hold the dock icon for Inkscape or XQuartz in your dock, and select “Show in Finder” from the pop-up menu. That will highlight the actual applications in use, so that you can verify that they are the correct ones.
