Wow, those are some crazy macros.

I am no macro expert, but can you have a /castrandom or /castsequence following a /castsequence in the same macro?? Also, I think both SWP and VT are on global cooldowns that's probably why you get that message. I am not sure, but you may have to choose 1 of the 2....or perhaps space them out so that 1.5seconds elapses?? Also, maybe put in some time for the reset so you don't have to have the spell listed 20 times? Make a list of your spells and find out how long the cooldown time is, if it's on global cooldown and how long the dots/channelling last. From there you should be able to work out an optimum timing on the reset and spell order.

Wish I could help more, but my fights don't last long enough yet (only L42 with my SP atm) (my macro is /castsequence Vampiric Embrace, Mind Flay, Mind Flay).

Good luck!