If you still have your old files in the "MLC_Favorites.txt" format then you shouldn't need to recreate anything.
Rename (or delete) existing Favourites key in registry.
Place desired MLC_Favorites.txt file into MLCad directory.
Launch MLCad - it will detect the non-existent Favourites key in the registry, detect the "legacy" MLC_Favorites.txt file and import it to the registry into a new Favouries key.
You could just leave it at that - follow the above procedure each time you want to switch favourites - and you could even automate the deletion of the key.
But since MLCad now can't write out an updated MLC_Favorites.txt file it might be a good idea to use RegEdit's export functionality to essentially one-time convert all your old .txt files one at a time into .reg files so that it becomes easier to update these existing files and apply them.
Rename (or delete) existing Favourites key in registry.
Place desired MLC_Favorites.txt file into MLCad directory.
Launch MLCad - it will detect the non-existent Favourites key in the registry, detect the "legacy" MLC_Favorites.txt file and import it to the registry into a new Favouries key.
You could just leave it at that - follow the above procedure each time you want to switch favourites - and you could even automate the deletion of the key.
But since MLCad now can't write out an updated MLC_Favorites.txt file it might be a good idea to use RegEdit's export functionality to essentially one-time convert all your old .txt files one at a time into .reg files so that it becomes easier to update these existing files and apply them.