BERLIN, July 29 (Reuters) - Germany is seeking 5.1 billion euros ($6.17 billion) in compensation for past delays to the launch of a nationwide truck toll, 500 million euros more than it had originally sought, the Transport Ministry said on Friday. Germany began charging trucks to cross its highway network, the busiest in Europe, at the start of the year, 16 months later than the initial planned start in summer 2003.