Another bump mapping question

I started experimenting with the bump mapping example in a test level and now I wanted to transfer the code into my real game. But it looks totally different than in the test level. With a bmap_to_normals amplification level of 2 there is no bump mapping at all and with a level of 2.5 or higher the texture is some kind of blurred (as if 2 bump textures were rendered on top of each other).
Maybe I initialised some engine vars with different values in both projects that's why I wanted to ask what engine variables influence bump mapping? Thanks.

I use min 4-6 , max 30 .
e.g.
bmap_to_normals(mat_bump.skin2,x);// x= 4-->30

bumpmapping's effect is clearly with these values.