Questions about the imagefield of CCK
assuming that you are talking about the 'edit form', you can use css to control the visibility of these fields in this way:


/*---------------------------this rule is to hide the text"maximum file size"and "allowed extensions"*/
div#edit-field-cl-namefiled-upload-wrapper div#edit-field-namefiled-upload-wrapper div.description{
display:none;
}

/*---------------------------this rule is to move your descriptionnear to the field to upload.here you can add the "allowed extensions.." text*/
div#edit-field-namefiled-upload-wrapper > div.description{
margin-top:-70px;
position:absolute;
}