map_file.gd line 140 Invalid access to property or key 'tile_z_index' on a base object of type 'Nil'

**Describe the bug** map_file.gd line 140 Invalid access to property or key 'tile_z_index' on a base object of type 'Nil' **To Reproduce** Steps to reproduce the behavior: 1. Download from github 2. Load by importing to Godot by importing project.godot 3. Hit run button in Godot **Expected behavior** run button should start the game **Desktop (please complete the following information):** - OS: Windows 11 - Game version 0.7.5