Rotation-strategy-based-on-Return-on-Interval-rebalanced-by-Day-of-Week

Hi, Guys! Really need your help, I'm trying to implement a simple rotation strategy. I looked at a few forum posts and tried to make my own:
A rotation strategy based on return for a certain interval, rebalancing by the day of the week, I also interested in whether it is more profitable to enter at closing prices or using market orders.
I'm confused by the gaps in the trades...I will be glad to receive any criticism, it is quite possible that since this is one of the first strategies on WL8, I did not take something into account...

CODE:
public class Rotate : UserStrategyBase
{
    public Rotate() : base()
    {
        AddParameter("ROC Period", ParameterType.Int32, 1, 1, 100, 1);
        AddParameter("Close Open", ParameterType.Int32, 0, 0, 1, 1);
        AddParameter("Day of Week", ParameterType.Int32, 1, 1, 5, 1);
    }

    //declare private variables below
    private TimeSeries avgROC;
    private string seriesKey = "Average ROC";

    //the list of symbols that we should buy each bar
    private static List<BarHistory> buys = new List<BarHistory>();

    //create the weight indicator and stash it into the BarHistory object for reference in PreExecute
    public override void Initialize(BarHistory bars)
    {
        StartIndex = Parameters[0].AsInt;
        avgROC = ROC.Series(bars.Close, Parameters[0].AsInt);
        bars.Cache[seriesKey] = avgROC;
    }

    //this is called prior to the Execute loop, determine which symbols have the lowest average ROC
    public override void PreExecute(DateTime dt, List<BarHistory> participants)
    {
        //store the symbols' AvgROC value in their BarHistory instances
        foreach (BarHistory bh in participants)
        {
            TimeSeries symbolRoc = (TimeSeries)bh.Cache[seriesKey];
            int idx = GetCurrentIndex(bh);  //this returns the index of the BarHistory for the bar currently being processed
            double rocVal = symbolRoc[idx];

            //if the indicator isn't valid set a high value to avoid selection in rotation
            if (idx < symbolRoc.FirstValidIndex)
                rocVal = 1.0e6;

            bh.UserData = rocVal; //save the current AvgROC value along with the BarHistory instance
        }

        //sort the participants by ROC value (lowest to highest)
        participants.Sort((a, b) => a.UserDataAsDouble.CompareTo(b.UserDataAsDouble));

        //keep the top 1 symbol
        buys.Clear();

        buys.Add(participants[0]);
    }

    //execute the strategy rules here, this is executed once for each bar in the backtest history
    public override void Execute(BarHistory bars, int idx)
    {

        // rebalance in certain days
        if ((int)bars.DateTimes[idx].DayOfWeek == Parameters[2].AsInt)
        {
            bool inBuyList = buys.Contains(bars);

            // first check if any position 
            if (HasOpenPosition(bars, PositionType.Long))
            {
                if (!inBuyList)
                {
                    if (Parameters[1].AsInt == 0)
                    {
                        PlaceTrade(bars, TransactionType.Sell, OrderType.MarketClose);
                    }
                    else
                    {
                        PlaceTrade(bars, TransactionType.Sell, OrderType.Market);
                    }


                }
            }

            // 
            if (!HasOpenPosition(bars, PositionType.Long))
            {
                if (inBuyList)
                {

                    if (Parameters[1].AsInt == 0)
                    {
                        PlaceTrade(bars, TransactionType.Buy, OrderType.MarketClose);
                    }
                    else
                    {
                        PlaceTrade(bars, TransactionType.Buy, OrderType.Market);
                    }

                }
            }

        }

    }
}