The formula that you are trying to backtest does not contain proper Short
and Cover rules. Short and Short rules should be written as assignments as
shown below:
Short = Cross( MA( Close, 50 ), Close )
);
Cover = Cross( Close, MA( Close, 50 )
);
If you do not want to test the short side, please go to the Settings and select Long from Positions combo-box.
This will allow you to test long side only.
For more details see Tutorial: Backtesting
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