There are 2 things I have found with building Pixel Maps lately, some celled fixtures with a Color XFade ie Skypanels can be put in a pixel map no problem, but others like Astera Titan Tubes in a celled mode with (ie mode 100,126,113) The Pixel map will not accept the cells or fixtures. This is largely a problem when working on a film set and want a Crossfade to CCT, but also need to be able to shift to an effect that would be made much easier and better with a pixel map.
Secondly I have noticed when working in venues with simple LED Fixtures ie the Generic RGB LED or ADJ UB12H, or seemingly any fixture with a Virtual Intensity, it doesn't respect the channels intensity, so if the pixel map is full and crossfaded to those fixtures will be full and running the pixel map with no way to inhibit or adjust intensity other than dimming the map, which makes balancing with other fixtures which can dim on their own rather difficult.