Can I change the order of the front matter (Dedication, Preface, Introduction and so on)?

Yes, from version 1.9.15. Open the book and go to the Export card on the right. Under "Include in book" every section has a small handle on the left and up and down arrows on the right: drag a section or use the arrows to put the front matter, and the back matter, in any order you like. The order is saved for that book and used by every export format and by the audiobook. Front matter stays before the chapters and back matter after them. "Standard order" at the top of the list appears once you changed something and puts everything back.