>How I can make the grid to change the backcolor of the current row...

You should use DynamicBackColor property. For example:

***Grid.Init event
local cLine
this.parent.grContRecno=-1
this.recordsource="tmpFrmeditL1"
this.colCalldate.controlsource="tmpFrmeditL1.calldate"
this.colUsername.controlsource="tmpFrmeditL1.username"
this.colCstatus.controlsource="tmpFrmeditL1.cstatus"
cLine="IIF(thisform.cntEdit.grContRecno=recno('tmpFrmeditL1'),65535,16777215)"
this.setall("Dynamicbackcolor",cLine,"column")
***Grid AfterColumnRowChange event
IF this.parent.grContRecno=recno("tmpFrmeditL1")
 RETURN
ENDIF
this.parent.grContRecno=recno("tmpFrmeditL1")
this.refresh
***Grid BeforeColumnRowChange event
IF used("tmpFrmeditL1")
 this.parent.grContRecno=recno("tmpFrmeditL1")
ENDIF