"Kataster Verschneidung" and "Flächenverschneidung" does not seem work

[myxBeni]

I struggled to get any meaningful results using either of the two boxes in the input dialogs "Kataster Verschneidung" and "Flächenverschneidung" in the lower half of the dialog. I assume it could be used to split the lines according to a polygon-layer (which would come very handy).