Ok, sadly the only thing you can do is go back to Court. You can sue for the damage, get them to remove the damage to the boundary and seek a Court order they remove the blockage of light.
You would need an injunction and potentially you could argue this was also harassment. That means they are indirectly harassing you for doing this.
You would need to complete form N1:
The Court would list the matter for hearing and decide whether to make the order making him take this down and stop harassing you.
If the Court makes the order and he breaches it, this is contempt of Court and he would be warned, fined or sent to prison.
However I am surprised the Council are not doing anything, this could be anti social behaviour - therefore they could look at this.
Can I clarify anything for you about this today please?