AFL coding -- Amibroker

Hello, I'm looking for help with AFL code to pyramid into trades. The money management would be very similar to the turtle trading money management. System rules: I want to enter a short position on new 20 day lows and scale into the position in 3 units. The 1st unit would have Van Tharp style stop loss (risking 1% of capital based on 2 * 20 day ATR) A 2nd unit would be added if the first unit shows a profit of 1 ATR. Stop loss on both units would then be set to a 1 ATR drop from 2nd unit entry price. A 3rd unit would be added if the first unit shows a profit of 2 ATR. Stop loss on all 3 units would then be a trailing 1 ATR from bars close.