>By the way, is the Vfp 5 wait command timing accurate ? Or do I
>had to use Win32Api insteads ?

I use the Sleep() API function if I want VFP to give up processor time and delay for a specific amout of time.

>Plus, having doevent() once every few hundred iterations of my
>processing loop actually prevent my user from action like stoping/exiting
>using the mouse/keyboard on my application. Is this problem cause by bad design, please advise me on this. Thank you.

Doevents is required so allow a user to do something like click a cancel button. If you are getting it to trigger you might need to call doevents more often.