I'm trying to get rid of an unwanted cut for a very simple test board.
The layout should look like this:

(screen shot of gerbv)

The gerber file looks very simple:
G75*
%MOIN*%
%OFA0B0*%
%FSLAX24Y24*%
%IPPOS*%
%LPD*%
%AMOC8*
5,1,8,0,0,1.08239X$1,22.5*
%
%ADD10C,0.0520*%
%ADD11C,0.0157*%
D10*
X001500Y001500D03*
X002500Y001500D03*
X002500Y002500D03*
X001500Y002500D03*
D11*
X002500Y002500D01*
M02*

With pcb2gcode V 2.5.0 and the following parameters
pcb2gcode --zsafe 5 --zchange 100 --zwork -0.05 --zcut -1.8 --mill-diameters 0.2mm --cutter-diameter 2.4mm --mill-feed 200 --cut-feed 800 --mill-speed 20000 --cut-speed 16000 --front millTest2-2bot-traces-GERBER_RS274X-1.gerber --basename millTest2-2bot-traces --metricoutput --vectorial 1 --software mach3 --optimise 0 --eulerian-paths 0

I got these cuts:

On the left hand side is the unwanted cut. Why is it there?
If I disable backtrack (using --backtrack 0) , it works fine:

Is it a bug or a feature? For bigger designs, backtracking might be very useful. I don't like to disable it entirely.

Thank you
Tobias