it hink this problem can be solved.Try go to descr_projectile_new.txt in data directory and change

projectile head

damage 0
radius 0.1
mass 0.15
min_angle 5
max_angle 70
velocity 25
display
model data/models_missile/missile_head_high.CAS, 40.0
model data/models_missile/missile_head_med.CAS, 80.0
model data/models_missile/missile_head_low.CAS, max

in

projectile head

damage 0.2
radius 0.1
mass 0.15
accuracy_vs_buildings 0.5
min_angle 5
max_angle 70
velocity 25
display
model data/models_missile/missile_head_high.CAS, 40.0
model data/models_missile/missile_head_med.CAS, 80.0
model data/models_missile/missile_head_low.CAS, max

let me know if it works