thanks a thousand! this is excellent and very complete tutorial..
On the dragon i have worked badly

but i have had this game from one week, must still learn; as you said, am going by intuition and modding experience in other games.
I had already done a magic addition,but at the beginning without animation
then I have made a modification putting the basic animation "priest2", but the signalling on the struck targets is not seen, he signals only a target but he strikes at least 3.
Code:
main {
class=chesspiece
model=priest2.bma
cullcat=0
}
arena_params {
features_label=cpi_priest_feat
.........................
attacks=moveattack,shot,respawn,holy_rage,firethrow
...............
firethrow {
dontusenearenemy=1
device=firecatapult
class=throw
picture=BA1_CatapultFire_
picture_small=BA1_CatapultFire_small.png
distance=50
ad_factor=1
base_attack=0
mindist=2
reload=4
penalty=0.5
animation=cast/throw/thtarget //animation change with basic animation priest2
throw=catapultfireball
hinthead=special_fire_catapult_head
hint=special_fire_catapult_hint
framekey=x
7in1=0.5
friendly_fire=1
damage {
fire=5,7
}
custom_params {
burn=25
}
}