How to make map in Gazebo

Hi everyone, I am trying to generate a map in Gazebo, then use Gmapping package to generate a 2D map of the environment. I use indigo which utilizes Gazebo 2.2. I figured out a way how to do so through Edit → Building Editor. However, every time I try to save the map Gazebo crashes. Is there any way that I can make a map in any other software and then import it to Gazebo2.2. ( I know I can use Gazebo5, which make it easy to generate a map, but unfortunately Gazebo5 is not compatible with indigo) Thanks, Shervin