Q: Dinosaurs have always been a problem for Christian theologians. What does the Urantia papers have to say about their purpose and creation besides to rip, kill and plunder each other, all according to God's plan of love?
A: Christian theologians often have many more problems than just with dinosaurs – -religious, scientific, and philosophical quandaries which The Urantia Book answers with logical, intelligent, thought provoking insight.
Christian theologians create a problem for themselves, in the explanation for dinosaurs for example, when they arbitrarily assume that all facts are contained in the Bible and that therefore everything must conform to what can be gleaned from the Scriptures, having decided that God created it all somewhere about 5, 000 B.C., and initially causing the rift between scientific inquiry and religion that resulted in the persecution and death of a number of notable scientists; a rift that persists today with many fundamentalist Christians. Knowledgeable Christians, like other knowledgeable religionists, accept the findings of science, just as knowledgeable scientists accept the truths of religion and a spiritual foundation to reality.
The cosmology of The Urantia Book explains that creation was put into motion before time began – -for us that would be well beyond trillions of trillions of years ago if we wanted to try to assign a time scale. One segment of creation was designated to become the origin place for life and that origin consists of seven enormous aggregations of matter – -clustered galaxies and stars – -of which the Milky Way is a part of one of those seven super universes, our solar system being a part of the Milky Way. The purpose of the cosmos is to provide the pattern upon which free will beings can originate and evolve and return to their source. It is created for that purpose – -the purpose isn't the purpose of matter (atoms and sub-atomic particles), or for star building, or for no purpose at all – -the purpose is for supporting and evolving the development of free will beings. Life is what it's all about. There was no mindless big bang – -it was all purposefully put into motion before time began. Some of this is explained in Paper 12—The Universe of Universes and in Paper 15—The Seven Superuniverses"
Our solar system is located on the fringe of the Milky Way – -an aggregate of matter that has been evolving toward order for the past 400 billion years. Five billion years ago the solar system began to form about our sun. Life was implanted on this planet (Urantia) 550 million years ago and that initial life implantation contained all the genetic code necessary for eventually evolving mortal beings of free will capacity which culminated approximately 1 million years ago in homo sapiens. Here we are!
An explanation for the discrepancy between the dates attributed by astronomers and geologists and the dates presented in The Urantia Book is available here
The evolutionary progression to human beings began with the implantation of living single cell plant life evolving to simple animal life then through more complex animal life to high primates and finally to human beings. Dinosaurs were an evolutionary step along that path toward evolving mammals. These sequences are scientifically delineated; the belief that life began with Adam and Eve 5, 000 B.C. and that the geological record is a hoax is ignorance; it disregards logical thought processes; a Scriptural explanation even neglects to explain how Cain found a wife in the land of Nod/
Your question appears to really ask why a loving God would allow beasts to prey upon one another. Another aspect of your question could be why would a loving God allow human beings to prey upon one another. Those would be topics for a different discussion.