thank you very much for your testings and info. Next thin I will do is checking the firmwareversion.

I noticed another effect/bug.

With a 400 steps per rev. Motor the canvas is 6400×1600 steps. If I use the hole area of 6400 steps

some parts of the drawing is shifted to another position. So this caused me to think that the software is “thinking” 

oh I’m near to one full revolution (which normally is 3200) I’ll do move optimisation and moving backwards to the new position. 

As long as I do a move that does only move the egg-axle everything is OK but if a try to draw some small rectangles

that are distributed over an area of 6400 pixels the rectangles that are beyond the 3200 steps border get misplaced.

If you tested the command SM this sounds like sending a single command to the EBB. Did you do some testing with the Inkscape-extension?

Is this problem located on the EBB or in the Inkscape-extension?

best regards  

 Stefan