- Select your light fixture family
- Click [Edit Type] in the Properties window
- Scroll down to "Photometrics"
- Select a higher Initial Intensity.
Feel free to try higher values, at some point you will see your light
Additionally to that, you can also go to the Enscape settings and increase the "Artificial Light Brightness" slider. It's in the "Advanced" settings tab in Enscape 2.5, and in the "Atmosphere" settings tab in the 2.6 preview.
Let me know in case there's further questions.