I learned how to do this, copy the downloaded theme to the new interface!
1) Do this for both the skin and the design folder ie ... / app / design / frontend / default / my _downloaded_theme / -> ... / app / design / frontend / myinterfacename / default
../skin/frontend/default/my_dowloaded_theme โ ../skin/frontend/myinterfacename/default
interfacename can be anything!
Now create a new theme and location folder (skin && design) in the same parent folder as the new default theme that you just copied.
In this case, I call it the main folder. The structure will look something like this:
.......... / interface / myinterfacename / Primary
So, under the myinterfacename folder, you should see the default folder and the main folder.
2) Log in to the admin and use myinterfacename / main as the default theme ....
this folder is empty, so it will revert to the default myinterfacename, which is the theme you downloaded that you just copied.
Now, for everything you want to change, just copy it by default to the new main folder and change it there.
Good luck !!!
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