something like this
Code:
alias countwindow {
  window -p @count 100 100 100 150
  drawtext @count 3 "courior new" -72 30 1 3
  .timerrecount 3 1 recount
}
alias recount { 
  $iif(!%number,set %number 2, dec %number)
  clear @count
  drawtext @count 3 "courior new" -72 30 1 %number
  if (%number <= 0) { 
    unset %number 
    clear @count
    window -p @count 75 50 600 350
    drawtext @count 4 "courior new" -72 100 110 BOOM! 
    .timercloseit 1 2 window -c @count
  }
}

maybe?