RIGHT, 345

 Code:
; begin KiXgolfUDF
;
;!
Function S($o)
  Dim $i, $, $k, $t, $x, $v, $p
  
  For $x = 0 to 16
    ReDim $r[3], $c[3], $q[3], $s[3, 3, $x]
    
    For $ = 0 to 7
      For $i = 0 to 3
        $v = $o[$ mod 4, $i]
        $k = 3-2*($<2)-($i<2)
        If $ < 4
          $r[$i] = $r[$i] + $v
          $c[$] = $c[$] + $v
          $q[$k] = $q[$k] + $v
          $s[$, $i, $x] = $v
        Else
          If 0 > AScan($r,x,,,1)
            Exit
          Else
            $p = @
            For $t = 1 to 4
              If 0 = InStr($c[$-4]+$r[$i]+$q[$k-2*($<6)],$t) + $v
                $p = $p + $t
              EndIf
            Next
    
            If 1=($p^)
              $o[$-4,$i] = $p
              $ = 7
              $i = 3
EndFunction

;!
;!
; end KiXgolfUDF
_________________________
!

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