Who is Luke Skywalker and Luuke Skywalker from The Last Command and what is their importance?

In the six years that have elapsed since the final Star Wars battle, Luke Skywalker has undertaken many missions on behalf of the New Republic. He is haunted by a battle with the dark Jedi Master Joruus C'baoth at Jomark where, deprived of the Force, he and Mara Jade narrowly escape. Luke regrets that he impetuously cut short his training under Jedi Master Yoda and often has to struggle using the Force.