Hi Boon Jin, (or anyone who would like to help),
I have been using the Smooth board for a while, it works perfectly, the only problem I have had is, it does not work on 1 of my 3 computers, but it works well on the other 2, unfortunately, it is this unlucky laptop computer that I use most often, it is very inconvenient for me to have to change computer when I want to play with the wiimote whiteboard, so I have done some tests with the problem today:
This unlucky laptop runs windows VISTA home premium, the other 2 computers run windows XP and windows VISTA home premium on each.
On the unlucky laptop, I can connect to the wiimote with WiimoteConnect, and Smoothboard can find the wiimote without a problem. But as soon as I've done the calibration, the software crashes and an error message pops up saying "Wiimote Smooth Board has stopped working" blah blah, and quits itself.
After some tests today, I have found some clue:
I've placed the software in different folders at different location on my laptop, I did notice that occassionaly for some unknown reason, when I moved the software to a different folder, it suddenly worked, I could complete calibration and use the whiteboard, but only for a while, if I restart the software again and again, eventually the same problem happens and I could not use it anymore.
Another thing I have found out is, if I do not calibrate but exit the software by clicking on the cross button or using the menu "File ---> exit", the software does not just exit right away as it does on the "good" computers, a dialog shows up saying:
"Unhandle exception has occurred in your application, if you click Continue, ....... If you click Quit, the applicaiton will close immediately
The process cannot access the file ".....\Wiimote Smoothboard0.4.6\WhiteboardCalibration.dat" because it is being used by another process"
And the dialog gives 3 buttons, if I click on Continue, the software will stay on, if I click on Quit, it will close.
See the error message screen shot below:

I never see the same dialog on the other 2 computers, and on the rare occasions when it works on the laptop, if I exit the software it does not show the error either. So I'm pretty sure this is the key.
I'm not sure if any other users have experienced the same problem, I'm not sure either if it is a problem with my laptop or the software, but I hope this could help Boon Jin make the software more reliably.
Thanks again for sharing the great software with us!