Maybe it's the incompatibility of multimod with the "new battle" mode. When trying to run a single battle, many generated soldiers get strange statistics, with parameters equal to one. The developer of the mod could not find the reason for this behavior.
Yes i was trying to fix the problem of the weird stats on single battles, but i was not able to found the problem. I think that i need to declare all stats for all soldier classes.
Therefore, it is better to play multimod as a normal game, without using the "new battle".