  In the first part of this paper, we obtain mirror formulas for twisted genus
0 two-point Gromov-Witten (GW) invariants of projective spaces and for the
genus 0 two-point GW-invariants of Fano and Calabi-Yau complete intersections.
This extends previous results for projective hypersurfaces, following the same
approach, but we also completely describe the structure coefficients in both
cases and obtain relations between these coefficients that are vital to the
applications to mirror symmetry in the rest of this paper. In the second and
third parts of this paper, we confirm Walcher's mirror symmetry conjectures for
the annulus and Klein bottle GW-invariants of Calabi-Yau complete intersection
threefolds; these applications are the main results of this paper. In a
separate paper, the genus~0 two-point formulas are used to obtain mirror
formulas for the genus~1 GW-invariants of all Calabi-Yau complete
intersections.
