Current questions and answers regarding the map editor.

Hello, when I was creating a map in the editor, I changed the textures and appearance of recruitable creatures in some buildings using the -Shared string. When I entered single-player mode, I noticed that the changed parameters apply to all maps and scenarios. Questions: Is this how it should be, or am I doing something wrong? And how can I make sure that such changes only apply to one specific map? (only with scripts?). Thank you in advance.