There a quite a few ways to run this quest. This is just a good pattern i have found for solo melees at level to get decent xp, decent return on goblets and loot as well as a fair run at time for 10-15 minutes.
A wiki overview of the quest can be found here:
http://ddowiki.com/page/Dr.%20Rushmo...ture%20Portals
1. Clear out the servants quarters for breakables before opening the first gate to maximize crests, if you find that fighting phantasms is sinking too much of your time avoid the pictures otherwise kill them quickly and move on. Find a pattern that works for you to hit every room efficiently.
2. Do not use any portals, it will affect your XP.
3. When you find the time foreman immediately sell him two minutes to reach the star objective and forget about him. Take speed boost and quad damage for best results. He will occasionally be beyond the first crested door on the topside of the Gallery.
4. Once you are past the first door find a pattern that works for you to efficiently pick up any crests that you can tab - target along your route. It is imperative that you find as many as you can along your way without backtracking. Do not get sidetracked by breakables that are not along your route.
5. Head through the south door and into the library, continue avoiding pictures if possible and collect visible crests along the route and nearby breakables, grab the crest in the ritual chamber if you see it.
6. If you can make yourself invisible do so and grab the crests on the topside of the bathhouse then head south through the crested door towards the backdoor. Shrine here if necessary.
7. If you can open locks gather crests from the locked doors in the backdoor, otherwise skip them. Drink a haste pot and run through the traps, fire resistance is helpful.
8. Clear out breakables at the end of the backdoor and into the entrance to the canal, drop into the canal water and collect up to three more crests from the bottom of the water.
9. Open the door to the assassins crib and kill the assassin, upstairs behind a secret door are two more crests.
10. Head back to the other side of the canal and east into the other backdoor. there are more traps here, at the end of the corridor take stock in your crests and make sure you have enough to open the door. Once you put a crest in the traps will go off.
If you do not have enough crests to open the door skip number 11 and go to 12.
11. Head east into the boudoir and kill the succubus. Make sure you have deathward against negative levels, elemental resists are helpful.
12. Hightail it back to the bathhouse, watch your hit points through the traps, use the shrine in the bath house if you didn't already. If you are short on time check your crests and open the door on the north east side of the bathhouse to extend your time. opening the door will also provide a small boost to your goblet return.
13. Detect secret doors on the east wall and head through the secret passage to the mother of the nest.
This run has a high level of consistency, rewards and average of 5,500 experience for 15 minutes runs on a level 16 character and rewards 1-3 chests and 100-250 goblets.
It is helpful (but not required) to have the following for this run:
Evasion or a decent reflex save
Open locks
Elemental resistances, particularly fire
Death ward or a silver flame amulet / talisman for non warforged characters.
A 30% striding item.
True Seeing / Detect secret doors.