What might help is if yeh change yer castsequence not to reset on target/combat but on time depending on yer longest cooldown spell

like
reset=30 Vampiric Embrace,Devouring Plague, Shadow Word: Pain, Vampiric
Touch,Mind Blast, Mind Flay, Mind Flay, Mind Flay, Mind Flay,Shadow Word: Death
This doesn't work, because the 30sec aren't count from your first activation of the castsequence, but is resetting every time you activate any spell in the castsequence and hence can't be used to reset exactly afeter 30sec.

actually it does work its there to reset for the next combat as in done killing stuff move to next area that way yeh always now what yeh start off with.
but since I didnt look at the cooldowns at the time figured 30 is good amount of time yeh could get away with it being lower like 10.