There were no written instructions, pictures only and a lack of labeling.  I wound up putting in the non-movable shelf upside down.  Trim was a nice look but it was also challenging to attach in a way that is secure and flush with the sides and top of the bookcase.  Doesn't seem as stable as I hoped for, even though I have put together numerous bookcases over the years and should have been able to do this one more easily.