hi,
Please open file "\CuteSoft_Client\CuteEditor\Dialogs\Tag\tag_image.ascx" and find section below, that is the browse button, the simple way is that hide this button and create your own button there, so you can achieve any function with the new button.
<input type="button" id="btnbrowse" value="[[Browse]]" class="formbutton" />
Regards,
Ken