The following lighting controls are present in Anim8or now:
1. Each lights color - can be animated with a controller.  Has been there for a long time.
2. Global lighting intensity - brightens or dims all lights.  Useful when there are a lot of lights and the scene is too bright such as  simulating various global effects.  New to v0.97c.
3. Gloabl ambient intensity - scales ambient lighting factor.  Set to 0 for completely dark shadows.  New to v0.97c.
4. Individual light's intenisty.  Animatable with controller "intensity" for each light.  
Not quite finished in time for v0.97c release - can't seem to fix a couple of bugs in it!  This will act like a dimmer for the light so you don't have to animate the color which is somewhat harder to manipulate than an overall dimmer control.  May be there for next prerelease if I can get to it.  (Don't hold your breath 

There is no "dimmer" control for the emissive component however.  I haven't decided what's really useful here.  I'd rather work on animated materials in general than to spend time on this.