Seems that if the plugin only uses the <kerbaldirectory>/parts and <kerbaldirectory>/plugins it works, but <kerbaldirectory>/plugindata does not Mechjeb 2.0.8 doesn't cause crash, ascent guidance still got me to LEO, isa map sat and kethane cause hangs at loading, version links below http://forum.kerbalspaceprogram.com/showthread.php/23979-Kethane-Pack-0-4-3-Download-link-now-up-to-date-after-forum-catastrophe http://forum.kerbalspaceprogram.com/showthread.php/12384-PLUGIN-PART-0-19-Anatid-Robotics-MuMech-MechJeb-Autopilot-v2-0-2 http://kerbalspaceprogram.com/isa-mapsat-3-3-4/