  Based on a set of cosmological N-body simulations we analyze properties of
the dark matter haloes (DM) in a galaxy mass range ($10^{11} - 10^{13}
h^{-1}M_{\odot}$) in modified $\lcdm$ cosmology with additional dynamically
screened scalar interactions in DM sector. Our simulations show that scalar
interactions support picture of the Island Universe. Rapid structure formation
processes are shifted into higher redshifts resulting in a much smaller
accretion and merging rates for galactic haloes at low redshifts. Finally, we
present how this "fifth" force affects halo properties, like density profile,
triaxiality, ellipticities and the spin parameter.
