http://www.pcgamer.com/2014/09/25/tri…to-public-beta/
Looks pretty interesting. I really loved Trine and Trine 2, especially in co-op.
They've also included some information about the editor on their wiki page:
Trine and Trine 2 editors released into public beta
Participate now!
Don’t have an account yet? Register yourself now and be a part of our community!