Hi, Forest aligns the items with the local axis of the own FP object. And the FP local axis depends of the way you created it.
1) If you create the FP object clicking a surface or a spline, FP inherits the local axis of the source object.
For instance, if your spline was created in the Front view, the FP object will be aligned in the front view as well.
2) If the FP is created using the "Icon" mode (without any reference), its axis is aligned with the view where you create it.
So, in this case you can create the FP object in the Front view (using the "Icon" mode), and asign later the spline.
Or if the spline is already aligned with the Front view, just create the FP object using the spline as reference.