Simple things.

[YinYin]

Hmmm, the get_closest function seems to be jamming.
It doesn't get the target properly, it usually takes one and doesn't change it.
The code looks ok for me, any ideas?

How do you know it sticks to one selected target? Are you loading your target before your other stuff?
The games basic AI selects it's own target and starts the ego function with it, so that might be the reason your target selection doesn't really do anything at all (or at least look like it).
Basically if you don't intend to do something special you don't have to select targets inside the ego function - it's easier to just work with the pre selected one.

Just wondering.
Is it possible to connect to someone who didn't install AI dll, while I do have it?
If possible how AI will react?

It is, but whenever two computer characters with different AI are fighting both games will run differently and get a sync error once the checksum (I think it works by checking the object hp only) on both games differs.