Heimer turret + stun Bug (4 problem)

1-when you cast turret(Q) near a tower if an ennemie walk and get hit the turret/inibitor doesnt attack anymore.. 2-The cast range on stun work 50% of the time sometime you just hit him and he just get slow.. 3-Sometime you cast Ult+Q and it just doesnt do anything... 4-When you cast turret(Q) or ult+Q and then die and being near a bush, if the ennemie just go in the bush even if its warded the tower doesnt make wave attack (usely even out of range wave are shot) :(