@PirateLord
Hopefully you've figured out how to use the "# of lights" feature in the shader tab in "render window properties" by now, since your post was a month ago, but now ya know. I was searching on how to block lights from one room to another and stumbled on to your post. Anyway, in the debug mode "# of lights", blue and green are good, purple is not so good, and when something is red, that's where you get the blinking lights. I hope you already figured that out (a month later), but if not that should help A LOT. I had the same problem until I started using the lights debug mode, now everythings good. Happy modding.
