2 Terrain Questions (Possibly for De Buurman)

Ok well this question is prolly something in De buurmans catagory but someone else might no...so here it goes...Well first of all these are demo questions.(And yes I have the full game too!) I shaded the only demo terrain ...but Ive seen some maps hosted by Red Scarf that you can actually drown in...And he also had invisible piranas attack the players...I think I might have a hunch how he did it though...Possibly packed the Ripple01 file from the fullversion game into the demo and it makes the water appear...for the host or whoever has it packed in there game...same deal with piranas ...But not sure anyone have any ideas what I could do to make it work?

Give me your comments :bouncing: