Siege Anamantarix - Am I playing it wrong?

I have to ask if I am doing anything wrong with the war engine i can never say or spell the name. So let me make sure I understand all of his stats.

1. He is a cavalry model so his charge attack also gets a boosted attack roll, that auto knocks down and hits at power 18.

2)He can then poke with the spears/and or shoot.

3. He doesn't have to shoot what he is engaged with.

4. He can then buy attacks with his rage tokens, on the auto knocked down model.

5. He is speed 8, so 11 inch charge + 2 inch reach.

6. He gets inherent pathfinder

7. He is a "beast" but not a warbeast. Which means he can be medicated but any anti warbeast tech doesn't effect him (dismember).

8. He can not shake status effects.