When did you expect it to fire? It fires when a TileEntity is created. And it definitely fires. Also are you wanting to attach it to every TileEntity in the game because if you only want it on your TileEntities that is not how you do it.
You should probably learn how.
ASM is not supported on this forum. Mainly because there are typically ways to do whatever you want with just the Event System and Reflection. What are you trying to do from an end user perspective.
I'm not sure if this still works, but you might be able to cast the ILightReader to a World(do an instanceof check it can be null). Then if it is use World::getTileEntity and store your colors in the TileEntity.
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