I am not sure how to explain it, but will try:
If my character dies with Magelight activated, it never goes away until zoning. Can remove it from the bar, switch bars, its still there. It is swirling around me, and my character sheet says its there. Also yesterday when I replaced it after it was buged, the new skill did not work properly. It looks like it just plain bugs the skill slot and the skill until zoning. So if this happens, I have no idea if it works afterwards, without me zoning and recasting.
Anyone else having this problem?