I found a small bug in the When() method of cGridlist, located in kcustctl.vcx. Here's the code:

*---------------------------------------
*--- Set the column controls' BackColor,
*--- ForeColor and SelectedBackColor
*---------------------------------------
FOR lnColumn = 1 TO This.ColumnCount
loControl = EVAL("This.columns[lncolumn]." + This.Columns[lnColumn].CurrentControl)
loControl.BackColor = This.nSelectedBackColor
loControl.ForeColor = This.nSelectedForeColor
loControl.SelectedBackColor = This.nSelectedBackColor
ENDFOR

The problem with the above code is that it assumes that you the currentcontrol supports the SelectedBackColor property. If you are using a checkbox, you will get an error. Currently, there are four controls that support this property: textbox, combobox, editbox and spinner.

I suggest testing the parentclass of loControl before attempting to set the SelectedBackcolor. This can be done with a custom method or simply an if statement. I used a custom method, but Kevin has the final decision on how the framework should deal with this minor problem. Thanks all!