The springs package contains a good node to create sublists of ‘joined’ curves with a specifiable tolerance value. Cant remember the exact name but it should be something like group curves.
However, i dont really understand what you mean by “i want to group parallel curves”, “1 and 4 are curved” and then they arent in the same sublist in the result?
Please redefine/ rephrase when to group curves in a sublist with other curves.