there is an INI file that is used by the SDK directory you need to delete that then reopen the SDK. You might have to reinstall the SDK after deleting it. We have covered this before so a bit or searching might turn it up. What has happened is that the props window is opening but is opening in a location not visible by your screen the opening location is in the INI. I think you might be able to edit the INI to like 0,0 for the props window and it will work.