Another that has not sewn the Library dress but I have made many outfit from for my children.
I adore sewing the stiffer silks, they are easy to handle and sew well.
First up, decide how you want to launder your garment, pre-wash and stick to that method. If you chose to hand wash ( wash in a shampoo solution and rinse in a conditioner solution) you will lose a little lustre and stiffness but it will be cheaper to maintain. Try washing a sample of the fabric to see if you find the result pleasing.
Mixing some salt with the water may help with colour fastness.
Silk can fray, so it may be worth cutting each piece as you intend to sew it.
You can sew all your finishes as a normal woven but hand sewing looks amazing and it worth the extra effort.
Definitely use the silk for the facing with a good quality interfacing. Under stitching is also helpful as it can prevent fray.
Good luck, I look forward to seeing what you make.