Maximum monsters' AC and DR

Hello guys,
I'm back with another question :
How can I limit the monster AC (armor class) and DR (damage resistance) ?
Actually, when a monster with a great magic/tech aptitude (magic 85) cast shield of protection and if he has some AC before (AC 15), it becomes "invulnerable" : it take negative damage when it's hit and make the player loose XP.
I guess it's because its AC or DR (basically 80 before the spell) become under the influence of the spell greater than 100.
I know that Drog fixed the fact that monsters' resistances are not limited in his patch but I have a french version and I can't use his patch. So could someone tell me how could I fix it by myself or just in what file it's coded (I could take that file form the UAP).
Thanks :thumbup:

 

Solved problem : it was on Arcanum.exe. I copied the file from the UAP, it doesn't cause any matter with a french version.