  The results of systematic calculations of isospin-symmetry-breaking
corrections to superallowed beta-decays based on the self-consistent isospin-
and angular-momentum-projected nuclear density functional theory (DFT) are
reviewed with an emphasis on theoretical uncertainties of the model. Extensions
of the formalism towards no core shell model approach with basis cutoff scheme
dictated by the self-consistent particle-hole DFT solutions will be also
discussed.
