Here is the amended complaint in Cherokee Nation of Oklahoma v. Nash (N.D. Okla.):

Cherokee nation vs nash 4 23 2012 Cherokee filing

From the motion for leave to amend:

The proposed Amended Complaint by the Cherokee Nation does not change the original parties, nor add causes of action. It changes the cause of action from a focus upon federal abrogation of the Treaty, to a focus on interpretation of the Treaty language as it was meant by the parties at the time, and as later interpreted by federal statute and cases.