yep that sounds about right!!
i appreciate you want your bike to run well, but without saying tough luck i think that although the chip should improve things if you shut off or slow down very quickly it can and will continue to do this
as i have said I adapted my riding anyway, but it has got noticeable better with age and deffo after running in ( i panicked when it first did it on the way homoe from picking it up!!) I now try to slow down much more and use the gears and it is much less likely to cut out although it still does it on idle at times.
If they cannot sort it your only option maybe to ask them to give you a 999r instead
I hope you get it sorted to your satisfaction
