ehhhm
I remember this one.
You have to start over again, go in the well again, free the fleeches, back in the well, then left, posses the Scrab, kill the fleeches and go back left, de-posses. When you are abe again, go back in the well, and run right. There should be a pressure pad or a ledge or something. Slap the Ghost-trap and run back to the well. If the scrab is in the Ghost-Trap screen, wait untill it is beneath you, do a running jump and run to the well and jump in the well fast.
Good luck
