Скрипт должен выставлять BUYLIM или SELLLIM на уровень указанный мышкой с величиной лота от заданного SL.

//+------------------------------------------------------------------+
//|                        Скрипт risk для МТ4   Mouse Lot SL TP.mq4 |
//|                        Copyright 2013, MetaQuotes Software Corp. |
//|                                          http://www.mункцql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2013, MetaQuotes Software Corp."
#property link      "http://www.mункцql5.com"
#property version   "1.00"
#property strict

#property show_inputs

extern double lot        = 1;
extern int    risk       = 10;
extern int    StopLoss   = 300;
extern int    Slippage   = 30;
extern double n          = 2;

extern int Magic         = 123;
int TakeProfit;
//+------------------------------------------------------------------+
//| Лот на стоп от депо                                              |
//+------------------------------------------------------------------+
double Lot(){
   double lt=lot;
   if(lot==0)
     {
      lt=NormalizeDouble((AccountEquity()*risk)/(100*StopLoss),2); 
     }
   return(lt);
  }
//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
  {
//---
   double StopLevel = MarketInfo(Symbol(),MODE_STOPLEVEL)*Point;
   double priceBuy = NormalizeDouble(WindowPriceOnDropped()-StopLevel*Point,Digits);
   double priceSell = NormalizeDouble(WindowPriceOnDropped()+StopLevel*Point,Digits);
   TakeProfit = NormalizeDouble(n*StopLoss,0);
   
   if(priceBuy<=Ask-StopLevel) 
      { 
       SetOrder(NULL, OP_BUYLIMIT, Lot(), priceBuy, priceBuy-StopLoss*Point, priceBuy+(StopLoss*n)*Point, Magic);
      }
   if(priceSell>=Bid+StopLevel) 
      {     
       SetOrder(NULL, OP_SELLLIMIT, Lot(), priceSell, priceSell+StopLoss*Point, priceSell-(StopLoss*n)*Point, Magic);
      }
   Comment("\n Lot: ",Lot(),
           "\n StopLoss: ",StopLoss,
           "\n TakeProfit: ",TakeProfit);
  }
//+------------------------------------------------------------------+
//|                                                                  |
//|                                                                  |
//+------------------------------------------------------------------+
void SetOrder(string sy, int op, double ll, double pp,
              double sl=0, double tp=0, int mn=0, datetime ex=0) {
  int   err, ticket;

  if (sy=="" || sy=="0") sy=Symbol();
  ticket=OrderSend(sy, op, ll, pp, Slippage, sl, tp, "", mn, ex, clrNONE);
  if (ticket<0) {
    err=GetLastError();
  }
}
//+----------------------------------------------------------------------------+