rhyell ... i had a problem stamping acetate at first ... it was more about the stamp skidding when i tried to lift it off after stamping
two things helped me ... one was to stick the acetate sheet down on to a craft mat so it didn't try and "follow me" when i lifted the stamp .. the other was to rub the acetate with an old tumble drier sheet before i stamped.
i honestly think these were both psychological helps because after i had done this a few times without smudging accidents, my confidence increased and it got easier to do!