You can set the amount you want to win per Dutching, as well as the range of ranks of selections to bet. I.e. the constant range_start defines the first rank in the range, and range_end - the last one. E.g. from the 2nd to the 5th favourite (in the trigger file it's 1-3 favourites).
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Gamble responsibly! Always be aware that betting is NOT risk-free. You must be 18+ years old before you try gambling, but even as an adult, withhold from spending money in an ill-judged manner. Our company does not encourage you to prefer gambling over other meaningful activities. If gambling is affecting your life or the lives of people close to you, please contact GamCare