If you are working with Maya 2016 and move to 2017, the Redshift lights disappears, its a known issue and the Redshift guys are fixing them.
On maya 2016.5 and higher, you need to set the Viewport 2.0 rendering engine to “OpenGL – legacy”, the lights also display correctly in the legacy and HQ viewport. (this is a known issue, on maya 2016.5+ the legacy lights are different but the guys on RS need to implement this..)
To set the Open GL to legacy go to:
1.Windows settings and preferences
2.look for display
3. on display go to viewport 2.0
4.Change the rendering engine from “Open GL – Core Profile to OpenGL – legacy
5. A promp should appear saying that you need to restart maya, click OK.
The downside from this is that you loose much of the great things from the Core profile.
The other way around is to jump between legacy mode and render 2.0 on the viewport render