If I understand you correctly, the rhythms (but not the note pitches) are exactly the same, right?

An idea (I have not tried it, but I suspect that it will work):

Copy the first measure to all the other measures.

Then, use the Simple Entry Tool’s sub-tool Repitch Tool to correct the pitches.

I suspect Peter's suggestion will work, but you need to factor in the time it will take to repitch all of the measures. That might take as long as moving the rests manually. 

What instrument is this for? I'm wondering if the layer 2 notes could be switched to layer one and delete the rests altogether.

Thanks for answering.

I have tried it out, and it is as You comment, Peters suggestion works fine, but it consumes almost the same amount of time as before. Only if one are well trained in using midikeyboard together with simple entry, the time elapse for repitching, will be a real difference.

The music is from a piano part. Yes, layer 2 could be put into layer 1. But there are two aspects here.

1: Readability. It is easier to read when the melody is separated from the rythmic part.

2: This is a copy of officially printed music. (I need it as base for an arrangement  I am about to make). That means that there is a given source. And as for all art work, one will give information about the source. If there are faults in the source compared to the original artwork, or discussion about what is original, or want to correct something, you also point out where changes have been made, and why. In other words: In this particular situation, I want the layers to be separated.

Børge, would using the 3rd layer for just rests work? You could use layer 1 for the top line and layer 2 for the line below and hide rests as you enter them in this layer. Then enter in only rests in layer 3, hiding the ones that don't need to be seen against layer 2. That way you would need to only adjust the rest vertical spacing one time for each of the spacing setups required and then copy and paste, with Show Active Layer Only, as needed.