openmw.org

In Glowbugs mod (https://www.nexusmods.com/morrowind/mods/50538) you can read:

"Note for OpenMW users: this mod does not currently work in OpenMW. The NIF does not seem to render properly. Most likely for a few different reasons. One of which being that OpenMW does not support explicit NIF controller targets like the vanilla game which is used to make the particle system work."

I think this may be important.

This has been tracked under issue #4811 for over 3 years. Not something trivial to approach, OSG doesn't have anything similar.

In the meantime, Fireflies Invade Morrowind is a pretty similar mod that does work.