Assuming the mouse cursor remains where it was, hidden... Let's say it was on item 2. Now using the keyboard you go down on item 15, and item 2 is no longer displayed. When you move the mouse it will highlight an item that is neither 15, nor 2. That could be more annoying than having to move the mouse by 2-3 cm to get it where it was.
You can calculate the parameters and move the cursor just right side the combo control, but I guess that will surely be annoying and discriminatory for the left hand user ;)

>>In the KeyPress method of the combo

mouse at 0,0 window 'formName'
>>dodefault(nKeyCode, nShiftAltCtrl)

>>
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>Thanks for reply,
>
>I thought of moving the mouse cursor too. But the user really expects the cursor to be where
>he left it, if not, he finds that annoying which defeats the purpose of satifying the user which is what I am trying to achieve here.