A new work by Joel Thompson takes its place amid an interesting collection of American and Mexican pieces on the Atlanta Symphony’s April 25-26 program. Lina Gonzalez-Granados conducts Gabriela Ortiz’s Kauyumari, Gabriela Lena Frank’s Walkabout: Concerto for Orchestra, and Arturo Márquez’s Danzón No. 2. Pianist Cédric Tiberghien will be the soloist in Gershwin’s Rhapsody in Blue.