The reason why it throws an error is because the current_room variable is set to None and that there’s no list of buttons called None_buttons
To be a little technical, the plugin tries to load buttons by looking at the current_room variable, adds _buttons to its value and tries to load the string result as a variable.
If you have a list of buttons (in the correct format) that ends in _buttons (ie. bedroom_buttons), the current_room variable must be updated to “bedroom” before jumping into the pnc_loop label.