In confined blue phases numerous quasi 2D disclination networks ranging from rings to double helices can be stable. We have recently demonstrated how such networks act as arrays of trapping sites that can lead to easy assembling of colloidal particles in complex 2D lattice structures. In this short overview we summarize main results of our Landau - de Gennes modeling combined with topology that was proven to be useful in bulk blue phase colloids. Effects of confinement, particle anchoring, and particle sizes that can range from micron to nanometre scale are presented. Quasi 2D colloidal crystals that can be easily manipulated by external stimuli via affecting liquid crystal and/or colloidal particles are expected to have possible photonic applications.