Run this script while in an area where are several NPCs. It will debug the MS positions of all NPCs, you can also run and rotate camera to test it better. 
SCAR Code:
program New;
{.include srl/srl.scar}
Var
TPA: TPointArray;
MSTPA: TPointArray;
T, I, L: Integer;
Procedure DrawBox(B: TBox; Time: Integer);
Var
T: Integer;
drawing : TBitmap;
Begin
drawing := TBitmap.Create;
drawing.canvas.handle := GetTargetDC;
drawing.canvas.Pen.Color := CLRED;
MarkTime(T);
Repeat
drawing.canvas.MoveTo(B.X1,B.y1);
drawing.canvas.LineTo(B.X2,B.y1);
drawing.canvas.LineTo(B.X2,B.y2);
drawing.canvas.LineTo(B.X1,B.y2);
drawing.canvas.LineTo(B.X1,B.y1);
Wait(2);
Until(TimeFromMark(T) > Time);
End;
begin
T := GetSystemTime + 12000;
While (GetSystemTime < T) Do
Begin
TPA := GetMinimapDots('npc');
L := Length(TPA);
SetLength(MSTPA, L);
For I := 0 To (L - 1) Do
Begin
MSTPA[I] := MMtoMS(TPA[I]);
If PointInBox(MSTPA[I], IntToBox(MSX1, MSY1, MSX2, MSY2)) Then
DrawBox(IntToBox(MSTPA[I].X-20, MSTPA[I].Y-20, MSTPA[I].X+20, MSTPA[I].Y+20), 20);
End;
End;
end.