Somehow I get the feeling that sneaking up behind Hraedsig and going “BOO!!” is not a good idea.
Let’s leave the room with the moving ceiling for the moment and find some Orcs so that a certain person can fulfill some urges he has towards them. 
Thoroncir also believes we should press on. We may investigate odd rooms and intriguing traps at our leisure when we’ve completed our task of clearing Goblin Gate of its foul occupants.
Ghân was thinking of the movable ceiling as a stone trap.
Sooooo…
twiddles thumbs
Orc hunting down the stairs then?
Yes! Let’s go!
:hums a jonty and, slightly off key, orc hunting tune (that he just made up right now) quietly to himself. He is really having a wonderful time. Orcs, trolls, goblins. Good times. 
:
“Lead the way, little scout.”
Sounds good to me. Let’s press on, and figure out who or what that last goblin was guarding.
The party heads down the stairs. The passage out of the little 10’ runs a long way off but there appears to be side passages off of it.
In which case, Mulligan explores the side passages while the rest of the party waits and we do them one at a time in order.
Might need to leave a few people in the main corridor as we examine each one depending what is there.
Wise plan.
All right, Mulligan, and thanks. Sir Thoroncir stands ready for whatever comes his way.
Mulligan and Elfstan begin checking the side passages. There are many and many alcoves. Mulligan works the left (south wall) and Elfstan the right (north wall). Gil-Gandel checks the first alcove with Gwaelur and Bitur for oddities and secret doors while waiting. The alcove is free of secrets but the Dwarves confer and estimate the walls are a few hundred years old and not of similar work to the tombs above.
Mulligan finds the first passage on the south is narrow and slopes down at a 30° angle. Parts of the passage are slippery. The passage is completely dark so sneaking is impossible. She goes about 100’ as the passage drifts east in a slow curve. Here she finds a door to the right hand side and the passage continues.
Elfstan find his passage goes 40’ and has stairs to the left and then 5’ later a passage sloping down.
Hmm,
Take a quick listen at the door and see if I can hear anything inside. I will probably need the rest of the party and some light to keep exploring the rest of the passageway.
Do the stairs that Elfstan has found, go up or down?
I think we should see what is behind this door and where this passageway goes before moving back to the stairs and the other passageway.
Any comments from the party?
Elfstan’s stairs head down and the Mulligan hears nothing behind the door.
Ok, Mulligan will check the door for traps, locks and then with the backup of a couple of heavy hitters, get the door open and see what is beyond.
I would suggest Elfstan explorers a bit further down the corridor round the bend.
Any note of evil/undead/Orcs in the area from those who can detect them would be useful.
Pulling Elfstan back with Sting, he still detects orcs in the area and closer as he approaches the door. There are no undead in the immediate area and no evil nearby.
The door is locked from the inside and is trapped. Mulligan makes short work of disarming the trap. She cannot unlock the door. It will require bashing or some other means.
" I think there are Orcs waiting behind this door. Who would like the honour of slaying them first. "
I believe bashing is someone else’s forte. While the rest are deciding who wants the honour, scout a bit further around, to make sure we are not going to get ambushed when the door is broken open.
Mulligan will be taking a torch. Not sneaky but she has a party of fighters backing her up and she is not afraid to use them. 
In mock “uppity Elf” voice (yeah, you know the type, present company seems to not have any of them, fortunately), Bitur pulls out his crowbar and says:
“Please, please. Bashing is sooooooo unsophisticated.” And starts to work on the door, enlisting the aid of however many can help grab the handle. (Probably only one other.)
Back to normal voice.
“Besides, the sound of axes and swords banging on doors tends to travel very well through stone hallways. I want to take out these vile abominations as much as the next dwarf, but if we can avoid bringing an army upon us, all the better. Discretion being the better part of valor and all that.”
BTW, the hinges aren’t on the outside of the door are they? 'Cause then we might be able to just disable the hinges. I mean, these are orcs after all…
If the crowbar fails, well than bashing it is.
Bitur and Gwaelur try to force the door. The crowbar digs in and begins cracking the stone frame around the door. The door itself is heavy aged oak and apparently thick and strong. The frame is dressed stone. The crowbar does not appear to be up to this job.
Mulligan finds the passage continues its gentle curve to the east. In another 40’ are two more doors opposite each other and the passage continues on.
So wise not to attempt the Elvish accent.
May as well try to pick or chisel out some of the stone door-frame as try to bash through well-aged oak, unless Ghân happens to be carrying a Warp Wood or Stone Shape of potency enough for the occasion, or Deor has a Knock about his person.