How to change Columns in Scan

Simply use
buysig = IIf(buycond, 1, 0); or
sellsig = IIf(sellcond, 1, 0); and so on

Filter = buysig == 1 || sellsig == 1 || .....

addcolumn(buysig, "BUY", 1.0, colorBrightgreen, colorBlack, 50);
addcolumn(sellsig, "SELL", 1.0, colorRed, colorBlack, 50);
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Or if you want the last true signal you could use writeif( buysig == 1, "BUY", "" ) ; and so on

Filter = Status("Lastbarinrange");

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