Hopelessly lost and infinitely embarressed Options

[worksfortheman]

I downloaded and got nej going. I've got my party through the severed hand and cleared out the entire place. I handed over all of the pieces of machine I found, but I think that I'm one short. I read the walkthrough, and have literally spent over 4 hours walking and rewalking through every room in the tower, holding the tab button and searching every single container, and I can't find the missing machine part(s). I've cleared all the tasks- from rebuilding the garden to freeing the souls of the soldiers. I've also tried retracing the steps of the walkthrough. At this point I'm desperate to move on. Is there any chance anyone knows the item codes for the machine parts? or the area codes/locations of them?
(setting aside those possibilities, given the chance that I had picked up all of the machine parts and then foolishly dropped one to make room for a two handed sword +1 and its somewhere I stand no chance of finding it, will I screw up my game if I movetoarea back to kuldahar and go through Arundel's portal without officially finishing the hand?)
Thanks for any help, and yes I feel like quite a fool...

[Golden Thief]

Did you get all 4 pieces? Here are the locations of the four pieces. If when you say tower and you mean the upper area then you are missing the first piece.

Spoiler
SPOILER!

The first piece is on the right side of the bottom level of the Severed Hand. You need to use the lift on the third floor to get to it.
A second piece is on the 3rd floor of Solonor Tower.
The next piece is on the 2nd floor of Corellon Tower.
Defeat all the elf warrior shades in Sheverash tower at Kaylessa's behest. Return to her and defeat her as she requests to get the final piece of machinery.

Is you conversation telling you that you still need another piece?