Arthur's Knights: SOM

Finished AK1 and now, with the help of a walkthrough have started the sequel, and am stuck even with the help. I've just left the King's Mound and spoken to Novelius about what has happened to Bradwen. I went back to Merlin's Tree to see if I could get elsewhere and none of the other roads are open. My walkthrough says there will be another road opened the other side of the tree and then the next Chapter tells me where I'll go. Am I supposed to do something before I go to the Tree. I have exhausted all the subjects with Novelius and I have no gifts to put in front of the tree or the three standing stones. HELP!!!