Final Fantasy Hacktics

Hi, i have a newbie question, i've searched in the forum but found no concret results, I have added Elmdor, Vormav, Kletian, Gafgarion and Celia to my party, and only Gafgarion have his own sprite in the formation and battle preparation screens, the others uses ramza sprites.
Okay, i just want to know, how i assign a sprite to the special characters, something like... kletian using kletian sprites in the formation.
I know. there's no sprite for these characters in the formation screen, but there is a method to link sprites and make then display the right sprites in the formation?
If there is a method, please, someone make a guideline for me, i don't know what to do in this case =x

Hi im new here in FFHackitcs, and im starting a custom project just to learn more about fft hack.
Ok, i tried to change few characters into another characters, like mustadio to alucard, just to test, but...
I've added alucard [mustadio] in the first battle, and when i reach the machine city, my alucard [mustadio] just leaves the party.
I've tried to edit the events in the machine city, but i've only found something like... Join after event, but i need to know, how to don't let the game dismiss my character after the event, can someone gimme a light?

~Sorry if i spelled something wrong, my english isnt perfect~