mIC doesn't work in the way other languages do. It can't call a dialog and hold processing for the return result. You need to use what Russel or Rand suggested. When th second dialog closes, return the information in the "on close event". I tend to make sure the dialog is open first. For example:

Code:
on *:DIALOG:[color:blue]info_dialog[/color]:close:*: {
  if ($dialog([color:blue]main_dialog[/color])) {
    /did -a [color:blue]main_dialog[/color] 100 blah blah
  }
}

-KingTomato