How to use custom OGRE materials in URDF in ROS Indigo that displays in Gazebo?

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Hi everyone

I want to create a custom OGRE material file, store it in my ROS Indigo package, and have my robot's visual in Gazebo use these materials.

I don't want to use SDF (I know how to; in fact, I learned SDF before URDF).

Here's what I tried and the results I got:

1. Using Gazebo's built in materials work.

   <gazebo reference="…">
       <material>Gazebo/Yellow</material>
   </gazebo>
   

2. Adding materials to Gazebo's built in materials file at /usr/share/gazebo-2.2/media/materials/scripts/gazebo.material also works.

3. This didn't work. It's for ROS Fuerte and Gazebo 1, so I had to make some changes:
   1. roscreate-pkg gazebo_tutorials std_msgs rospy roscpp gazebo failed because ERROR: dependency [gazebo] cannot be found. I installed through apt-get every package that had gazebo in the name, but that didn't fix it. So, instead, I replaced gazebo by all packages returned by rospack list that started with gazebo. Only after the package was created that I realized it was the command to generate the old package format. This and this pages confirm that rospack find gazebo used to work in the past and doesn't anymore. So I created a new package and replaced the <depend> tags by <build_depend>, <buildtool_depend> and <run_depend>.
   2. I tried with <gazebo gazebo_media_path="${prefix}" /> but, when launching the package, Warning [Visual.cc:819] Unable to get Material[…] for Geometry[…. Object will appear white. Then I replaced ${prefix} by the full path to where my ….material file was located; same result.
4. The first snippet from the answer to this question results in Warning [Visual.cc:819] Unable to get Material[script] for Geometry[…. Object will appear white. Note it says script instead of the material name. I tried several variations for <uri>'s argument.
5. This confirmed a suspicion that the ….material file must be inside a Media folder, so I'm testing with and without it.
6. This led me
   1. here, but adding the <env> tag to the launch file also didn't work. Because find gazebo doesn't work anymore, I'm using "$GAZEBO_RESOURCE_PATH:$(find …)". I'm not certain if it makes sense.
   2. and here. There's two ….material files and one ….urdf file that uses one of those materials, but this file isn't used anywhere. Also, the syntax is strange. It says <material>b21.material</material>, which is the name of the file, but the materials defined there are named b21_base_dark and b21_base_blue. These names aren't used anywhere. I also tried to place my ….material file in the full Media/materials/scripts path as is used by this package. manifest.xml only confirms to me that "${prefix}" is correct, but I don't know what's the impact of not having the gazebo package anymore.
7. I don't mind using a colored Collada file if it worked. I applied random face colors with MeshLab. Mesh is still white. In RViz, it's a darker gray. Adding an <ambient> tag as per here ...