Thank you, thank you everybody for the feedback 
Yeah, as Nidal say, I have been slow but thanks to you all, at least I know now that I am moving in the right direction judging by the positive comments.
By the way, when you kill a zombie, its corpse does float in the water in the editor, but in the coocked packaged game it doesn’t…
For the water I am using a Fluid surface actor movable , when the zombies are killed they are replaced with KAssets, and in order for them to float in the water. I am using a nxgenericforcefieldbrush volume. Looks like the nxgenericforcefieldbrush is not working in a coocked and packaged game?It doesn’t work even if I play the game from frontend before packaging.
Has anyone experienced this?