The improvements in PhotoLab 6.3 mainly target the Elite edition, with an extension to the soft proofing tools that can no incorporate on-screen simulations of papers and inks, to allow even more accurate color visualization and control over printed output.
Working space (color management)
Color spaces describe the range of colors and device can display, and during photo editing it's common to use a larger 'working space' to incorporate the full range of colors you might need. Some working spaces are purely mathematical and not used by any actual devices.
Color spaces, profiles and color management explained
The whole topic of color management can get pretty dry and technical, but stick with it because there’s information here that’s useful and puts lots of other things in context.