Nice thx,
Now my code looks like this:

////////////////////////////////////////////////////////////////////
#include <acknex.h>
#include <default.c>


////////////////////////////////////////////////////////////////////

ENTITY* wizard;

////////////////////////////////////////////////////////////////////


}
function main()
{
//video_mode = 7; // 800x600 pixels
video_switch (8,32,1);
level_load ("Drohne_Levelc.wmb");


}a

action wizard_with_pointer()
{
wizard = my;
my.ambient = 100;
while(1)
{

c_move(my, nullvector, nullvector, GLIDE );
my.x += 5 * (key_a - key_d) * time_step;
my.y += 5 * (key_s - key_w) * time_step;
my.pan += -50 * mouse_force.x * time_step;

camera.x = my.x;
camera.y = my.y + 100;
camera.z = my.z + 15;

camera.pan = my.pan + 270;
camera.tilt = - 12;

c_move(my, nullvector, nullvector, GLIDE );
wait(1);
}
}

action wizard_simple()
{
my.ambient = 100;
}

My Problem is that the model moves absolutly and not relative.
Does anyone have a solution which doesn't need to change my code completly?