Unfortunately, you can't claim credits for costs in 2011 because the statute for filing a claim has expired.  Adoptions credits can only be claimed in the year following payment or the year the adoption is final, whichever is earlier.  Under that rule:

• 2011 expenses would be claimed on your 2012 return,  The statute for refunds expired April 15, 2016.
• 2012 expenses would be claimed on your 2013 return,  The statute for refunds expires April 15, 2017.  Make sure you file a claim for refund for 2013 (for costs paid in 2012) on or before that date.