If you want the emissive material to actually cast light into the world you must be running the 4.6 or newer build of the engine.
Make sure your material setup has the **Emissive **port going into a Multiply which has A as a 3Vector (Color) and the B as a 1Vector (Intensity) - Make your intensity something like 10 or higher, i would recommend creating an instance and parametizing the Vectors for easier adjustment.
Also make sure that in your Material properties you have Emissive (Dynamic Area Light) checked.
The last thing to do is select your Mesh and under it’s properties go to Lighting > Lightmass Settings and check Use Emissive for Static Lighting and make sure your mesh is set to the default transform mode of Static under the Transform tab of the mesh properties.
Now build your lighting and once it’s built click the tab in the top of the view port that says Lit and change it to** Lighting Only** then back to Lit, your Emissive material lighting should now be there - Once you do this for the first time you do not have to go back and change the lighting mode from Lit to Lighting only again.