How do you add mixed units to a map?

It seems this question has already been raised on the forum, but no one has given a constructive answer. Most likely, this can only be done with scripts, here: http://all4heroes.net/node/515, study it.

Added 8 minutes later

Hello everyone. Please help. When working with the editor, the computer gives the following errors:
Object and craig intersection: 57:37, ground floor.
Object and craig intersection: 58:37, ground floor.
Object and craig intersection: 58:38, ground floor.
Object and craig intersection: 59:38, ground floor...
What do they mean and how can I fix them?!:confused:

My English isn't very good, but judging by this, I can say that somewhere on the map, objects are sinking into the ground, meaning it will be impossible to approach them, or, for example, a Castle on a hill, but there is no way to descend from it. Be more careful when creating the map, and you won't have these problems ;) .