You have great ideas in this piece. Yet it's rather rough as it doesn't quite fit the ambient genre with so strong melody.
+overall feeling
+parts 0:53-01:09 and 01:39-01:52, good ideas but as said, bit rough on the edges :)
-first minute feels bit dragging, maybe a slight variation to the basic melody would keep it fresh
till the first transition?
-Rough on the edges, but easily fixed
3 stars from me, keep working on it! :)