EDIT: Please ignore this.
With mip-mapping enabled, some GPUs (such as my Intel integrated graphics) cause a visual bug with indexed textures that use alpha. This bug has been present for a while but not noticed before. All indexed alpha textures in MTGame will now be converted to RGBA.
We advise that in your mods you use RGBA mode for any texture that contains transparent or semi-tranparent pixels. You may wish to convert your existing textures.