I've just extracted some files, but a lot of them appear as .import files. How do I make them viewable?
This is how Godot works. It converts the original assets into a format that is more convenient and compact for the engine itself. Inside the .import file is a path to the converted file in the .godot folder. You can open this converted file using a compatible version of the Godot Engine or use another tool that can convert the compiled game into a decompiled project.