diff --git a/addons/resources_spreadsheet_view/import_export/formats_edit/edit_tres.gd b/addons/resources_spreadsheet_view/import_export/formats_edit/edit_tres.gd
index eb19696..e5e4ccc 100644
--- a/addons/resources_spreadsheet_view/import_export/formats_edit/edit_tres.gd
+++ b/addons/resources_spreadsheet_view/import_export/formats_edit/edit_tres.gd
@@ -55,6 +55,7 @@ func has_row_names():
 func import_from_path(folderpath : String, insert_func : Callable, sort_by : String, sort_reverse : bool = false) -> Array:
 	var rows := []
 	var dir := DirAccess.open(folderpath)
+	if dir == null: return []
 	dir.list_dir_begin()
 
 	editor_view.remembered_paths.clear()
diff --git a/addons/resources_spreadsheet_view/main_screen/input_handler.gd b/addons/resources_spreadsheet_view/main_screen/input_handler.gd
index a32dfea..52bd9ea 100644
--- a/addons/resources_spreadsheet_view/main_screen/input_handler.gd
+++ b/addons/resources_spreadsheet_view/main_screen/input_handler.gd
@@ -58,18 +58,7 @@ func _input(event : InputEvent):
 	
 	# Ctrl + Z (before, and instead of, committing the action!)
 	if Input.is_key_pressed(KEY_CTRL):
-		if event.keycode == KEY_Z:
-			if Input.is_key_pressed(KEY_SHIFT):
-				editor_view.editor_plugin.undo_redo.redo()
-			# Ctrl + z (smol)
-			else:
-				editor_view.editor_plugin.undo_redo.undo()
-			
-			return
-
-		# This shortcut is used by Godot as well.
-		if event.keycode == KEY_Y:
-			editor_view.editor_plugin.undo_redo.redo()
+		if event.keycode == KEY_Z || event.keycode == KEY_Y:
 			return
 
 	_key_specific_action(event)
diff --git a/addons/resources_spreadsheet_view/main_screen/selection_manager.gd b/addons/resources_spreadsheet_view/main_screen/selection_manager.gd
index 203ebd3..b5261a9 100644
--- a/addons/resources_spreadsheet_view/main_screen/selection_manager.gd
+++ b/addons/resources_spreadsheet_view/main_screen/selection_manager.gd
@@ -13,8 +13,8 @@ const EditorView = preload("res://addons/resources_spreadsheet_view/editor_view.
 
 @onready var editor_view : EditorView = get_parent()
 
-var edited_cells = []
-var edited_cells_text : Array[String] = []
+var edited_cells := []
+var edited_cells_text := []
 var edit_cursor_positions : Array[int] = []
 
 var all_cell_editors : Array[Object]
@@ -52,7 +52,7 @@ func _draw():
 
 		var char_size := Vector2(0, font.get_ascent(font_size))
 		var cursor_pos := Vector2(label_padding_left, 0)
-		var cell_text := edited_cells_text[i]
+		var cell_text : String = edited_cells_text[i]
 		var cell : Control = edited_cells[i]
 		if cell is Label and cell.horizontal_alignment == HORIZONTAL_ALIGNMENT_RIGHT:
 			cursor_pos.x += cell.size.x - font.get_multiline_string_size(edited_cells[i].text, HORIZONTAL_ALIGNMENT_RIGHT, -1, font_size).x