Andre,
it looks like the construction layer feature is activated on some layers.
In LibreCAD 2 you activate a construction layer by disable printing in the layer list. All lines become infinite on such a layer. Enabling printing again shows the lines in their original length.
Find the printer symbol in the layer list and toggle it to see the effect.
If you want a layer not to be printed, you have to freeze it before printing, this is done with the eye icon in the layer list, then all entities on that layer are hidden on screen and printing.
Armin
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