EditorScript - Texture set isReadable, and yet not accessible

Unity 3.4.0 - Editorscripting

Hi,

I wrote an Assetpostprocessor editor script, in which I need to change some texture options.
All works well except Reading a texture.

If anyone has a suggestion, idea or knows if this is perhaps a known bug.

My implemented procedure:

1/ I set the texture's TextureImporter.isReadable to true

string path = AssetDatabase.GetAssetPath(tex);
TextureImporter texImporter = AssetImporter.GetAtPath(path) as TextureImporter;
texImporter.textureType = TextureImporterType.Advanced;
texImporter.textureFormat = TextureImporterFormat.ARGB32;
texImporter.isReadable = true;

2/ I reimport the asset with forceupdate as a parameter

AssetDatabase.ImportAsset(path,ImportAssetOptions.ForceUpdate);

3/ I do a security check to make sure the texture is set to readable

Debug.Log("Texture is readable: "+texImporter.isReadable);

=> Unity returns a positive value, meaning it is indeed Readable and so I enter my if statement

if(texImporter.isReadable==true){

4/ I try to read the texture

CMcol = tex.GetPixels();

=> Unity crashes the import and gives me a "is not readable" error for the texture. If I reiterate the import, the first texture goes fine. This time around he can really read the first texture on which he crashed last time, but crashes on the second texture, and so forth... Has anyone encountered and solved this issue? Any help would be appreciated.