If you select some perviously drawn object ( e.g. a line, circle ... ), you should be able to
1) change it line properties (e.g. thickness, color)
2) change it shape ( e.g. move the end points )
3) move it from one layer to an other
It looks like that it is not currently possible ( in LibreCAD 1.0 ), is it? If it is, please send me a link, I dindn't foud anything in help, wiki, or in menus.
... I think this is pretty basic feature in most of 2D CAD or vector drawing programs, so I wonder if it realy is not present.