The fabrication of "magnetic" two-dimensional electron gases in modulation-doped ZnSe/Zn1-x-yCdxMnySe quantum wells and superlattices is described, with a focus on correlating growth conditions with low temperature transport, atomic force microscopy, and photoluminescence. Optimization of the growth parameters results in a two-fold increase in 0.3 K mobility (similar to 23 000 cm(2)/V s) for the host ZnCdSe two-dimensional electron gasses (2DEGs) and a similar relative increase for magnetic 2DEGs. The improved sample growth is applied to the fabrication of modulation doped, strained-layer magnetic superlattices containing up to 25 periods of moderately strained quantum wells, without significant reduction in mobility.