For the pension splitting, CRA tells me that Social Security from the USA cannot be split between spouses, but this program wants to do this, why?

If you are entering your US Social Security Benefits on the "Foreign Income" slip page in TurboTax, they will post to Line 115 of the tax return, but will not be eligible for Pension Splitting. 

Enter these benefits by going to Income > T-Slips > Foreign Income.