The technology level of a Perry Rhodan setting would be beyond
even the technology level of the Ancients of the Third Imperium
setting, so one would have to design the entire technology part
of the rules, for example new rules for starship drives and weapons,
instant interstellar communication and matter transmission,
or various types of force fields and screens. A typical small craft
in the Perry Rhodan universe is a spherical craft with a diameter
of 60 meters, the size of a Third Imperium warship, and a huge
battleship of the Perry Rhodan universe has a diameter of 2,500
meters, which Traveller's starship design rules could hardly handle.
And so on and on, these are just two examples of many.