aline -a @kick . | dline @kick $line(@kick,0)

^ add a line , and select it (moves the scroll bar down) then delete the line.

Code:
on ^*:kick:#:{
  if ($nick == $me) && ($knick != $me) { /window  -el @kick Lucida Sans Unicode 14 | aline @kick 0,1You kicked $knick | aline -a @kick . | dline @kick $line(@kick,0) } 
  if ($nick != $me) && ($knick == $me) { /window  -el @kick Lucida Sans Unicode 14 | aline @kick you were kick by $nick | aline -a @kick . | dline @kick $line(@kick,0) }
}