Mike,
I am having the same/similar problem, but there is no code firing (at least I don't believe there is). It occurs just tabbing/arrowing around the grid.
Any ideas?

>Hi Cathy,
>
>>When I refresh my grid after processing some code in the dblclick() method of a column, it quickly flashes an empty grid with an all gray background and then repaints my grid with the new data.
>
>Don't know what causes it, but if you do:
>
>

thisform.LockScreen = .T.
>Normal code
>thisform.LockScreen = .F.

Does it fix it?