Which version of Corona, which host software (including version), and which OS? Did you re-render after baking the lights? Have you checked the lights individually to see what their color and intensity settings are after baking? Are you sure you are viewing the Beauty pass, and not somehow the LightMix pass (which may or may not exist now)? What happens if you add a new light, does it show up as expected and illuminate the scene, so only the baked lights are having problems? Can you share a video of the process, or the scene, or at least some screen grabs (seeing the LightMix tab, seeing the render before baking, seeing one of the lights after baking to show intensity and color, may be useful here)?
Thanks!
Tom