This is the code i’m using, seems ok:

// Definition of code parameters
DEFPARAM CumulateOrders = True // Cumulating positions deactivated


if abs(countofposition)>1 then
if longonmarket then
sell at positionprice limit
else
exitshort at positionprice limit
endif
endif

// Prevents the system from placing new orders on specified days of the week
daysForbiddenEntry = OpenDayOfWeek = 6

m = 0.4

ONCE positionsize = 0.5


// Conditions to enter long positions
indicator1 = williams[14](close)
c1 = (indicator1 CROSSES OVER -80)

IF NOT LONGONMARKET AND c1 AND not daysForbiddenEntry THEN
BUY positionsize PERPOINT AT MARKET
ENDIF

//let's add another order while price continue to get lower (more than 10 points) than the last order taken with a condition of 1 bars elapsed since then

IF LONGONMARKET AND TRADEINDEX>1 AND close-TRADEPRICE<-20 THEN
Buy PositionSize * (1 + (countofposition * m)) perpoint at market
endif

// Conditions to exit long positions
indicator2 = williams[14](close)
c2 = (indicator2 CROSSES UNDER -20)

IF c2 THEN
SELL AT MARKET

ENDIF

IF COUNTOFPOSITION > 0.5 AND Close > POSITIONPRICE THEN
SELL AT MARKET

ENDIF


// Conditions to enter short positions
indicator3 = williams[14](close)
c3 = (indicator3 CROSSES UNDER -20)

IF NOT SHORTONMARKET AND c3 AND not daysForbiddenEntry THEN
SELLSHORT positionsize PERPOINT AT MARKET
ENDIF

//let's add another order while price continue to get higher (more than 10 points) than the last order taken with a condition of 1 bars elapsed since then

IF SHORTONMARKET AND TRADEINDEX>1 AND close-TRADEPRICE>20 THEN
Sellshort Positionsize * (1 + (ABS(countofposition) * m)) perpoint at market
endif

// Conditions to exit short positions
indicator4 = williams[14](close)
c4 = (indicator4 CROSSES OVER -80)

IF c4 THEN
EXITSHORT AT MARKET

ENDIF

IF COUNTOFPOSITION < -0.5 AND Close < POSITIONPRICE THEN
EXITSHORT AT MARKET
ENDIF

graphonprice positionprice

The white line on the price chart is where the orders should close when accumulating.

close-on-average-price.png