Hi & welcome to Seamly2D Forum, @danijel100
The SeamlyME is a measurement file where you store the measurements that are taken from the person or article and it is used in Seamly2D, not the other way around.
If you read this post, Reference of segment length and creation order of draft blocks, I explain the order of things in the pattern file saving. So, affectively, since the measurement file is one of the first in the list, line lengths aren’t available in the measurement file, so there’s no point in allowing SeamlyME to have that option.
I hope this helps 