Problem getting a script to function like I want it to

#==============================================================================
# ＋＋ 8-Direction Characterset Edit ver. 1.01 ＋＋
#  Script by ParaDog
#  [URL]http://2d6.parasite.jp/[/URL]
#------------------------------------------------------------------------------
# Additional 'diagonal' movement is now possible by pushing combinations of the
# vertical and horizontal controls (up & left, etc) simultaneously.
#
# Additional charsets for the 8-directional movement are to be stored within
# the "Graphics/Characters" folder, just like the regular charactersets.
#
# Name the new diagonal movement charactersets the same as the regular ones,
# but with a new '_quarter' extension. As such, you would name the very first
# characterset: 001-Fighter01_quarter.
#------------------------------------------------------------------------------
# Additional notes:
# This system can be used with the 'Dash Characterset Edit' system, but please
# place this script 'BELOW' the fore-mentioned Dash script for it to work.
#
# As you can combine the two scripts (Dash and 8-Directional), you can also use
# charactersets that show diagonal running action, also stored within the same
# "Graphics/Characters" folder.
#
# Naming the new graphics would require the inclusion of both '_dash' and the 
# '_quarter' extensions as shown here: 001-Fighter01_dash_quarter.
#==============================================================================
#==============================================================================
# ** Game_Player
#------------------------------------------------------------------------------
# This class handles the player. Its functions include event starting
# determinants and map scrolling. Refer to "$game_player" for the one
# instance of this class.
#==============================================================================
class Game_Player < Game_Character
 #--------------------------------------------------------------------------
 # * Frame update
 #--------------------------------------------------------------------------
 alias update_para_quarter update
 def update
 update_para_quarter
 unless moving? or $game_system.map_interpreter.running? or
 @move_route_forcing or $game_temp.message_window_showing
 # If the direction button is pushed, move the player in that direction
 case Input.dir8
 when 1 # Move Lower Left
 move_lower_left
 when 3 # Move Lower Right
 move_lower_right
 when 7 # Move Upper Left
 move_upper_left
 when 9 # Move Upper Right
 move_upper_right
 end
 end
 end
end
#==============================================================================
# ** Sprite_Character
#------------------------------------------------------------------------------
# This sprite is used to display the character.It observes the Game_Character
# class and automatically changes sprite conditions.
#==============================================================================
class Sprite_Character < RPG::Sprite
 #--------------------------------------------------------------------------
 # * Frame Update
 #--------------------------------------------------------------------------
 alias update_para_quarter update
 def update
 update_para_quarter
 if @tile_id == 0
 if (@character.direction - 2) % 2 == 1
 # Checking the presence of the diagonal charset
 if quarter_graphic_exist?(@character)
 # Set the diagonal charset
 if character.dash_on and dash_quarter_graphic_exist?(@character)
 @character_name = @character.character_name + "_dash_quarter"
 else
 @character_name = @character.character_name + "_quarter"
 end
 self.bitmap = RPG::Cache.character(@character_name,
 @character.character_hue)
 # Acquire direction
 case @character.direction
 when 1
 n = 0
 when 3
 n = 2
 when 7
 n = 1
 when 9
 n = 3
 end
 else
 @character.direction = @character.sub_direction
 # When the diagonal charset does not exist, direction
 n = (@character.direction - 2) / 2
 end
 # Set original transfer rectangle
 sx = @character.pattern * @cw
 sy = n * @ch
 self.src_rect.set(sx, sy, @cw, @ch)
 else
 self.bitmap = RPG::Cache.character(@character.character_name,
 @character.character_hue)
 # Set original transfer rectangle
 sx = @character.pattern * @cw
 sy = (@character.direction - 2) / 2 * @ch
 self.src_rect.set(sx, sy, @cw, @ch)
 end
 end
 end
 #--------------------------------------------------------------------------
 # * Diagonal Charset?
 #--------------------------------------------------------------------------
 def quarter_graphic_exist?(character)
 # Reading check
 begin
 RPG::Cache.character(character.character_name.to_s + "_quarter", character.character_hue)
 rescue
 return false
 end
 return true
 end
 #--------------------------------------------------------------------------
 # * Dashing Diagonal Charset?
 #--------------------------------------------------------------------------
 def dash_quarter_graphic_exist?(character)
 # Reading check
 begin
 RPG::Cache.character(character.character_name.to_s + "_dash_quarter", character.character_hue)
 rescue
 return false
 end
 return true
 end
end
#==============================================================================
# ** Game_Character
#------------------------------------------------------------------------------
# This class deals with characters. It's used as a superclass for the
# Game_Player and Game_Event classes.
#==============================================================================
class Game_Character
 #--------------------------------------------------------------------------
 # * Public Instance Variables
 #--------------------------------------------------------------------------
 attr_accessor :direction # direction
 attr_accessor :sub_direction # sub_direction
 #--------------------------------------------------------------------------
 # * Move Lower Left
 #--------------------------------------------------------------------------
 def move_lower_left
 # If no direction fix
 unless @direction_fix
 @sub_direction = @direction
 @direction = 1
 # Face left if facing right, and face down if facing up
 @sub_direction = (@sub_direction == 6 ? 4 : @sub_direction == 8 ? 2 : @sub_direction)
 end
 # When a down to left or a left to down course is passable
 if (passable?(@x, @y, 2) and passable?(@x, @y + 1, 4)) or
 (passable?(@x, @y, 4) and passable?(@x - 1, @y, 2))
 # Update coordinates
 @x -= 1
 @y += 1
 # Increase steps
 increase_steps
 end
 end
 #--------------------------------------------------------------------------
 # * Move Lower Right
 #--------------------------------------------------------------------------
 def move_lower_right
 # If no direction fix
 unless @direction_fix
 @sub_direction = @direction
 @direction = 3
 # Face right if facing left, and face down if facing up
 @sub_direction = (@sub_direction == 4 ? 6 : @sub_direction == 8 ? 2 : @sub_direction)
 end
 # When a down to right or a right to down course is passable
 if (passable?(@x, @y, 2) and passable?(@x, @y + 1, 6)) or
 (passable?(@x, @y, 6) and passable?(@x + 1, @y, 2))
 # Update coordinates
 @x += 1
 @y += 1
 # Increase steps
 increase_steps
 end
 end
 #--------------------------------------------------------------------------
 # * Move Upper Left
 #--------------------------------------------------------------------------
 def move_upper_left
 # If no direction fix
 unless @direction_fix
 @sub_direction = @direction
 @direction = 7
 # Face left if facing right, and face up if facing down
 @sub_direction = (@sub_direction == 6 ? 4 : @sub_direction == 2 ? 8 : @sub_direction)
 end
 # When an up to left or a left to up course is passable
 if (passable?(@x, @y, 8) and passable?(@x, @y - 1, 4)) or
 (passable?(@x, @y, 4) and passable?(@x - 1, @y, 8))
 # Update coordinates
 @x -= 1
 @y -= 1
 # Increase steps
 increase_steps
 end
 end
 #--------------------------------------------------------------------------
 # * Move Upper Right
 #--------------------------------------------------------------------------
 def move_upper_right
 # If no direction fix
 unless @direction_fix
 @sub_direction = @direction
 @direction = 9
 # Face right if facing left, and face up if facing down
 @sub_direction = (@sub_direction == 4 ? 6 : @sub_direction == 2 ? 8 : @sub_direction)
 end
 # When an up to right or a right to up course is passable
 if (passable?(@x, @y, 8) and passable?(@x, @y - 1, 6)) or
 (passable?(@x, @y, 6) and passable?(@x + 1, @y, 8))
 # Update coordinates
 @x += 1
 @y -= 1
 # Increase steps
 increase_steps
 end
 end
 #--------------------------------------------------------------------------
 # * Dash
 #--------------------------------------------------------------------------
 def dash_on
 if @dash_on != nil
 return @dash_on
 else
 return false
 end
end
end