zchin, check the CA thread. I have a solution posted there for your problem.
sf, Have you ensured you set your weapons user animation as the 'attack anim' animation id? If not, that is likely your problem.
death by moogles, You may have the same problem as SF. You might also just ensure that the battler includes the name ANIM in the filename. I believe it is required to be all upper case as displayed, but I dont remember.
Sobeman459, Half of the system is designed around the status containing a certain character etc. However, that said, it isnt required. You would simply adjust the status window in section 3(I think) in order to display all actors info and simply take and ignore the other data that would normally be passed to it. This would allow it to be compatible without adjusting the actual battle system.
As for the threat system, it is already there, but only subtly. There is currently no way to adjust it at this time without getting knee deep in the code. There is a battle definition (section 4) that is called rate_action which will look at various things such as range/attack type/expected damage/expected effected members/heal percents etc that all factor into the decision made on what the 'rating' is. If there is no possible targets it assigns a 0 to the rating making it impossible to be selected. This is the only place I recommend you look.
Can you list some games that uses this script?
http://www.creationasylum.net/forum/ind ... opic=25560
If there are any other questions I missed, just let me know.