The default behavior of the Assistant on Mac 10.11. with Apple Mail App is now to replace existing profiles.
In the Past it was possible to add every profile with the assistant and all profiles showed up in the Apple Mail Client. Now only the first profile can be added over the Assistant, every additional profile has to be added manualy, otherwise with the Assistant, the first profile is overwritten by the next added over the Assistant. I was told by support, that this is now normal behavior regarding to the Apple Mail App in Mac OS 10.11. It would be great, if the Assistant would behave like in the past.
The Kerio Account Assitant is worthless to me because we can't customize what settings get added. I do it all manually now.