In "In the Shadow of War," how do you interpret the details that Omovo sees on the riverbank, such as the unfinished estates?
Well, the short answer to your question is that every quote is important - what we are presented with in short stories is a very concise choice of words carefully crafted together to achieve a specific effect. Okri in this excellent short story is keen to present us with a realistic picture of a war-torn post-colonial African nation still bearing many of the scars of its colonial past. Consider this quote which includes some of the details you mentioned:
He passed unfinished estates, with their flaking, ostentatious signboards and their collapsing fences. He passed an empty cement factory: Blocks lay crumbled in heaps and the workers' sheds were deserted. He passed a baobab tree, under which was the intact skeleton of a large animal.
Notice how the word choice or diction gradually builds up a picture of a decaying, abandoned and deprived nation: "unfinished", "flaking", "collapsing", and "empty" clearly paint a picture of the kind of colonial legacy that has been left and is plaguing so many African countries, whilst the inclusion of a skeleton that has lain there for so long adds a slightly menacing, threatening note, as well as indicating the kind of place this is - no one clears away dead animals - they are left to rot. In this arena of disregard and neglect, acts of violence are able to be committed and become part of every day life.