1) there are one-way arrows on top of the gifts.
2) it does say it will reset? seems clear enough.
3) it is explained in the general rules that you can attack through killer neutrals in trench games.
1) Yes, but it's easy to believe the arrows are there to help you find the gift on the tree - they are colour coded and pointing in different directions. They certainly do have the function I just mentioned, so no-one should automatically assume they have a second function which could easily have been clarified in the notes.
2) It does say it resets - but it says it does so "after being occupied", which I and others have taken to mean at the end of your turn. The re-write of this that I suggested takes up no extra space and makes clear when it resets.
3) Yes, I missed that. Thank you.