Thanks for your concerned. Actually I would like to have twetytwelve child theme istall to my computer so that editing will be easier before uploading.
For your info, I have to do it again from scracth cos prior to this my resigned wed designer have not wp backup. Since the last two weeks our site was bruce attack
I got no choice to asked our hosting to reformat the cpanel. And now new wp installation is in the cpanel including the child theme .
The thing went smoothly until I got stucked at style.css.
Scenerio: I download the ie.css folder in twentytwelve/ie.css to my local computer and upload again to twentytwelve-child/ie.css.
Still at the lower bottom of my admin>theme listed the message Broken Themes
The following themes are installed but incomplete. Themes must have a stylesheet and a template.
twentytwelve-child Stylesheet is missing.