Thanx for the hints!

LOD for the models (Add mipmapps in MED) already in use.
Do you know a better way if the models mesh (vertexnumber) is fix?

Reducing time-consuming methods is a good idea.
There are some of them i can eliminate. (e.g. i use scan_entity to activate the distance-alarm - i will change it to vec_dist();)
There are other possibilities too for shure...

thanx, mercuryus