I realize you're showing a fox trick, but here's something that can go in the KeyPress which will give the correct effect:

*-- If this is a lower case letter
IF BETWEEN(nKeyCode,ASC("a"),ASC("z"))
    *-- If it is the first letter or a letter after a space
    IF this.SelStart=0 OR (this.SelStart>0 and SUBSTR(this.Value,this.SelStart,1)=" ")
        *-- Uppercase the letter
        NODEFAULT
        RETURN DoDefault(nKeyCode-32,nShiftAltCtrl)
    ENDIF
ENDIF

*-- If this is an upper case letter
IF BETWEEN(nKeyCode,ASC("A"),ASC("Z"))
    *-- If it is the not the first letter or a letter after a space
    IF !(this.SelStart=0 AND (this.SelStart>0 and SUBSTR(this.Value,this.SelStart,1)=" "))
        *-- Lowercase the letter
        NODEFAULT
        RETURN DoDefault(nKeyCode+32,nShiftAltCtrl)
    ENDIF
ENDIF

>I think because it's resetting the "SelStart" value.
>
>>Thanks for the Stupid FoxPro Trick, John. :)
>>
>>You also can have fun simply with
>>
>> THIS.Value=THIS.Value
>>
>>in InteractiveChange. Wonder why it does that??