It's rather simple, really.
JKSetSaberInfo is the best way to make lightsabers glow in a stationary position (at least, to my liking since it always faces the camera and only clips on the tips, and not the sides.) I used it for the stationary lightsaber blades.
The motion blur itself is a 3do. The saber is set to invisible while the motion blur is active, and returns once the saber stops.
With both combined, it gives an amazing feel ingame, I really like how it turned out.
I currently have motion blurs for the Quigon saber and the Anakin saber. I'm working on the rest.
I was unable to use the stretched lightsaber for the motionblurs due to issues with the sabercore. The saber mat is always facing a certain way, but the core deviates from this. It just looks out of place. (a.k.a failed experiment.)
I might be working on the mats to give the core a little bit of a glow to it.