Tested th is with Warlocks and Drain Soul. AMAZING. Works like a dream! Had to of course name the folder properly and put it in the right place

Only thing it fails on is Hellfire. Which does not break follow anyway but is generally being cast once combat is over and the game reports you are too busy to follow right now. I would imagine this would also fail on Rain of Fire and Blizzard as well as any other channeled spells that did not end on out of combat (e.g. not drain life or arcane missiles, etc).