Hey man, sorry nobody's answered this yet but five months late isn't too terrible for a necro-post. Based on what you've stated I figure it's an issue with how you're creating your lights. If you make lights from scratch all of the variables are set to zero so just setting the Radius isn't going to be enough, the Fade box in the section where you set the color coding for the light needs to be something higher than zero or you'll just get that little pinpoint or "bug" of light. The factory Bethesda settings for lights varies between four categories: ambient, fill, key and kicker, with ambient lights being the faintest and kicker lights (spotlights) are the brightest. The Fade setting controls how far said light projects, ambient lights have a Fade setting of 1, fill lights are a little higher with a 1.25 Fade setting, key lights jump to 1.8 for the Fade setting and the brightest kicker lights are set to 2.4 for the Fade. Since you've set the Radius to 300 I'd recommend between 1-1.5 for the Fade setting for a decent approximation of how much light the lanterns should emit.
Based on your computer's specs it might not be an issue but if you're not already aware lighting can cause serious in-game lag based on how many are placed inside of a single cell, so I've found for interior cells it's best to use a couple lights with higher radius/fade settings than multiple weaker lights.
Edited by RichardIsADeadMan, 22 March 2019 - 01:38 AM.