Credit Suisse has joined Redwood Trust to push the comeback of the non-agency MBS sector with a new public issue, while Springleaf Financial has put together another securitization backed by seasoned subprime mortgages. The Credit Suisse transaction, CSFB Mortgage Securities 2012-CIM1, is backed by $1.4 billion of prime residential mortgages, 82 percent of which had been originated by MetLife Home Loans. The deal sparked some controversy among rating services as Fitch Ratings questioned whether it had enough credit enhancement to cover risks related to property valuations on many of the...