I just tested it on the blend i reported, and it seems to work correctly, thanks for the update.
edit : tested on some rather complex geometry and it still cut greatly.
now post some cool stuff using the addon, so we could add more buttons in there 
oh and thnx piotr, gotta add one more button on the panel this coming saturday.
Playing a bit with it
Using the Grease Pencil in “Polygon” setting (CTRL+D and Right Mouse click)
And Grease Cut
Very cool now it works more reliably, thanks Iceking and Piotr
Hey! Thanks you guys for this tool! It is a timesaving, really. 
Just out of curiosity, it could be possible to add to this something more precise as the ruler tool instead of the grease pencil?
Of course, I don’t actually mean the ruler tool but something as it that, may be, also implements a bezier curve like the Path Tool from Gimp.
Btw, I’m just asking if it is possible and not that you should make it possible. 
Yes, it is. It should be possible to use both bezier curves and simple vertex meshes made of a few vertices stringed together with edges as rulers. I’ll probably do that next.
Done. You can now cut with simple geometry and bezier curves. I wonder what I should rename the button to now that grease pencil is not the only option anymore.
It’s really great !!
That is awesome, Piotr! Thanks!
jeeeeeez! thankyou, this is amazing!
Improved the reliability of the grease cut, fixed cutting with edge-string type objects.
sorry to be pushing so many updates, but stuff just keeps cropping up
It’s good to have updates ^^
Thank you very much for that update, with the curves it’s simply amazing !
I’m going to try it ~
Edit: It’s awesome.
Another small update: you can now cut holes with the grease pencil - if the endpoints are close together, the stroke will become cyclic.
Not sure this will really be all that useful for actual work, but since someone asked in the other thread, there you go.
Piotr, you seems to be a good and reactive dev, have you another script/addon or have you thinking of making other scripts ? Or maybe add some features to blender ?
Thanks, but I’m just a fellow user. There’s some other stuff I’d like to see in Blender, but I don’t think I can implement it. At least not without spending a lot of time studying - and I don’t have that much time.
ok I understand ^^