Chuck S, thanks for your suggestions. But you cannot imagined what happened! Ha..haa... I followed the installation instruction, the one with directory permission setting and left out uploading the
JS folder.
I redownload the build and compared with the ones I have in my server and found the
JS folder missing. I have since uploaded it and WYSIWYG is working all good now.
Re-uploaded the "template" folder and everything is looking good now.