>I put the setall() in the init event of the grid.
>
>The expression is as follow:
>
>this.setall("DynamicBackColor", "this.setbackcolor()", "Column")
>
>setbackcolor is a function I add to the grid class.
>
>
>setbackcolor()
>
>if status.selected
> return RGB(255,0,0)
>else
> return RGB(255,255,0)
>endif

Try w/o method call.

this.setall("DynamicBackColor", ;
  "IIF(status.selected, RGB(255,0,0), RGB(255,255,0))", ;
  "Column")