The Prokeimenon looks fine. The only orthographical inaccuracy is that the ison for the word "God" in line 5 can't have an oligon beneath it because it is not followed by another ison. That oligon should be replaced by a petaste.
As for the Orthros Idiomelon, I couldn't find any mistakes. But I do wonder if you have chosen the right word to emphasize in the phrase "cease not to intercede". You have chosen to emphasize the word "not", but I am thinking that perhaps the word "cease" should be emphasized instead. Maybe someone else would like to offer their opinion, too.