MartinFa said:
AMS/CRS is not an ingredient: it's a blend of acids
Anything that goes into a product to be consumed by humans is an ingredient. This includes "salt to taste."
As a "blend of acids" it's nondescript, as nothing is provided to base a calculation upon. Instead, there's just a rough addition amount. Besides, I think they're probably comprised of some very cheap mineral salts, which is very different than acids. One might simply substitute the minerals mentioned and achieve a usable result.
BeerSmith Misc ingredients allow for calculating dose based on volume. Since a range amount is all that's provided for AMS (nothing for DWB) this can be adjusted in the recipe to reflect the actual amount needed.
The link shows AMS's impact on alkalinity, not pH. BeerSmith 3's water function does calculate alkalinity, which is not the same as pH. So, the mineral contribution of a specific dose need to be entered for BeerSmith 3 to calculate the alkalinity.
Usually, ingredients like AMS & DWB are formulated for a specific set of starting water specifications. Unless you have those specifications, all bets are off about how well your results will match their predictions.
Personally, I find it effective and easy to just weight out minerals for mash and boil and add them directly. I add minerals for flavor impact, not mash pH. Then I can choose the exact acid I need to adjust pH and get further changes to mineral ions.
I don't want you to think that I'm dismissing these products. Rather there is a lot of missing information about them that would make me change my answer about where they belong in BeerSmith. A major point to me is that I don't know the other half of the ions they're showing. Is it Calcium? Probably. But it could be sodium, potassium or something else. Is there an actual acid in it? Dunno and would have to do the guesswork based on the alkalinity reduction but even then, I can't be sure because I don't know the other ions.