Using the last release (rev48) or using SVN the application process will NOT DIE after closing it! kill -9 sometimes works and sometimes does not.
Most of the time SVN closes on it's own. In fact I can't repeat the problem with SVN.
Rev48 Never closes on it's own. The process always hangs.
There will be a new OXM release soon; in the meantime please continue to use the latest SVN revision.