I have what I think is the fragmnet..a metal contraption, tagged as a querst item but the quest will not complete...anyone? This a bug? Only thing left behind the guys house is a trap door I cant unlock so I must have the piece...

I believe it is used in Kayran trap diagram (sold by Cedric). Not sure what you mean by "quest will not complete" though, in fact I think there is no quest that is explicitly associated with it.

The Kayran trap is an optional item that you can use against the Kayran.

True. Whether you have the piece or not just need to climb up and peek through the open window Shíle leaned out from before, and the quest continues.

Making the trap later makes the Kayran fight slightly shorter.

TY,
I went out front but the find fragment quest is still active..will restart and look in the window

If you can be more specific about the quest that would be very helpful. The word "fragment" and "the guys house" (Loredo) isn't very explanatory.

Perhaps what you have is a ballista fragment? The item for Kayran trap might be Iron Frame.