Additional information is given in the attached mission.
On YouTube I have uploaded the beginning of the mission. You can see it on
http://youtu.be/8SEhOgmXCP0
(Duration: 3:40 min. First plopping effect: 1:40 min.)
Making this video I realized, that 'plopping' is more a kind of 'glitching'. But this happens realy fast and sometimes through walls, so that plopping still fits better.