@Makro as @ErikMatthezing wrote:
at MRA-Routeplanner (web page), in the list of your routes, there is a tick box in front of each row, By ticking this box(es) you can select several routes, then you will see at the bottom of the page, the context menue (as shown above).
But there is also a tick box in front of the headline of list (it's not easy to see - you need to mousover to make it visible). But if you tick this tick box - all list itel will be ticked in one bunch. Then you may deselct some of, if needed).
That makes clean up work easy