In this paper we describe a padtage XMOD [8] of ftmctions for computing with crossed modules, their morphisms and derivations; caP-groups, their morphisms and sections, written using the GAP [7] group theory programming language. We have also enumerated the isomorphisnı classes of cat'-groups in [1,4] and [2], We gavethe application algorithms and sonıe mathematical results on cat'-group structures in [3], We also made a computational conıment on pre-crossed modules, pre-cat'-groups and underiying grupoids in this paper.