I'm genuinely sorry to hear this. Very sorry indeed. We have to respect the law and copyright, but I didnt see the harm a free mod based on Skyrim or Oblivion would do harm to anyone in any way.
Do what I did with Mesogea. Make up an entirely new world and storyline and go for a TC. I decided on Mesogea a long time ago (1986 to be precise as a novel that is well under way) only knocking up a game for fun on a ZX Spectrum was a bit pants to say the least. Make sure you do what I did record absolutely everything to completely prove entire ownership. Put it in a letter and send it to yourself, date stamped. Then keep it. It's more interesting to invent your own world and YOU own it! With a great team (youve already got one) you can do some fantastic stuff. Tolkien based much of his work on Germanic and Nordic mythology (though there is a lot of classical stuff in there too). Classical mythology has provided a wealth of content for Mesogea and it's been great fun since the mid 80's writing the story, inventing the world and the story lines. Go for it. Whatever is done with the CS has to be property of Bethesda, fair's only fair, but your models, textures, story and all that goes with it, are your own to license as you see fit. No more worry over C&D letters (unless you want to send your own out

if some big film company nicks your stuff)