I remember being able to do this up till version 0.4. To use the steam overlay, all you did was add the launcher to your steam games list and launch it, and when MWLL is launched, the steam overlay would work on it. This is no longer the case. Now, after launching the launcher, and launching MWLL, the overlay closes with the launcher.
I hope this makes sense to anyone using steam, and if so is there some sort of workaround to fix it?