Right, Sarlona-specific culture regarding d-doors, sorry, what I'm talking about with common ddoor at part 5 is on Thelanis PuGs, I think nearly every completion I have we have the ddoor/drop group for those not completing w/a countdown for the altar.
Here's the thread I highly recommend for puzzle solving:
http://forums.ddo.com/showthread.php?t=228976
with the practice tool that does not have a "solve" feature and does not generate unsolvable puzzles from that thread at: http://terpstra.ca/vale.html
With buffing do not buff after part 4, you'll lose all buffs transitioning to part 5 and the lost sp will mean you'll be running back and forth over the corner of the healing pool that much longer.
Right, in part 5 while the kiting is going on you may spend some time with the cleric(s) running back and forth over the corner of a pool to refill your sp. I don't usually see the arcanes doing this step-shuffle, but sometimes.