This is addressed in the mod description on the workshop page. Usually a good place to look for information about a mod.

I indeed read the description the exact moment I decided to download the mod, and I'm well aware of the """fix""" by setting up the default classes and setting "custom classes" to "off".
BUT there has to be another way: if the bots consider the M1911 as the default weapon MAYBE something can be done about it, like changing what they think it is the default weapon to another one like the M1 Thompson.

1911 replaces fists as default if nothing is equipped.
Default classes are set up in the mod, but bots don't like to use them for who knows what reason. If you don't have time to take a minute to set up the guns for them, then you probably don't have time to play the mod so not sure why you're making a big deal about it. It's a very small amount of time compared to the amount of time I put into making the mod work as well as it does.

Usually it's not a big deal, as I like to set up matches like "Americans vs Germans" or "British vs Russians" and giving the two teams completely different classes, but it would be nice for once to simulate an online match with custom classes, that's all.

I think you should make the default a thompson or a mosin nagant