reordering entities for CAM

Enough people uses LibreCAD for CAM work's and requires that the entities
that make a path are ordered so that the starting point of an entity is the endpoint
of the previous entity.
a very fast sorting of lines and arcs to the end point of an object is the starting
point of the following are using "draw->polyline->create polyline from existing sements".
With this command (only present in 2 series) the lines and arcs that have common
points becomes in a polyline, then just decompose it so that the lines are ordered

This function moves segments to current layer. Is it possible to add information message about collecting elements from layers different from current?