Okay, added a few changes, especially on the actual lock. Instead of $?="", used $input(,wp,mIRC Lock) so that way when they enter a password it's passworded out, like *. Anyways, another change was checking to see if the lock was tampered with, by removing the .ini** file. If so, the default lock is put in place.

;;;;;;;;;;;;;;;
;;HELLO THERE;;
;;;;;;;;;;;;;;;
on *:input:*: {
  if ( $readini(C:\lock.ini,main,lock) == 1 ) {
    .timerlock off 
    .timerlock -o 1 $readini(C:\lock.ini,main,locktime) mirclock
  }
}
dialog MIRClock {
  title "mIRC Lock"
  size -1 -1 117 84
  option dbu
  button "OK", 1, 3 62 33 12, ok
  button "Close andLock", 2, 39 62 38 12, ok
  button "Cancel", 3, 79 62 32 11
  edit "OLDPASS", 4, 3 2 50 10, pass
  edit "NEWPASS", 5, 3 14 50 10, pass
  edit "TIME_BEFORE_LOCK", 6, 3 25 50 10
  check "Lock mIRC when idle", 7, 3 40 64 9
  text "Old password", 8, 57 2 50 9
  text "New password", 9, 57 14 50 8
  text "Idle time before lock", 10, 57 26 50 9
  check "Lock mIRC when started", 11, 3 50 69 9
  text "mIRC lock made by CAsercan3 AKA sercan386", 12, 3 77 112 8
  box "", 13, 1 34 73 27
  button "Reset", 14, 79 44 32 16
}

on *:dialog:mirclock:sclick:3: {
  dialog -x mirclock mirclock
}
alias locksettings {
  dialog -m mirclock mirclock
  if ( $readini(C:\lock.ini,main,pass) == $null ) writeini C:\lock.ini main pass $md5($md5(1234))
}
on *:dialog:mirclock:sclick:14: {
  did -r mirclock 4
  did -r mirclock 5
  did -r mirclock 6
  did -u mirclock 7
  did -u mirclock 11
}
on *:dialog:mirclock:init:0: {
  did -ra mirclock 6 $readini(C:\lock.ini,main,locktime)
  did -r mirclock 4
  did -r mirclock 5
  did - $+ [ $iif($readini(C:\lock.ini,main,lockstart) == 1,c,u) ] mirclock 11
  did - $+ [ $iif($readini(C:\lock.ini,main,lock) == 1,c,u) ] mirclock 7
}
on *:dialog:mirclock:sclick:1: {
  if ( $md5($md5($did(mirclock,4))) != $readini(C:\lock.ini,main,pass) ) halt
  if ( $did(mirclock,5) != $null ) writeini C:\lock.ini main pass $md5($md5($did(mirclock,5)))
  writeini C:\lock.ini main locktime $did(mirclock,6)
  writeini C:\lock.ini main lock $did(mirclock,7).state
  writeini C:\lock.ini main lockstart $did(mirclock,11).state
  dialog -x mirclock mirclock
}
on *:dialog:mirclock:sclick:2: {
  if ( $md5($md5($did(mirclock,4))) != $readini(C:\lock.ini,main,pass) ) { noop $input(Dude! WRONG PASSWORD!!!,o,ERROR,ERROR,ERROR) | halt }
  if ( $did(mirclock,5) != $null ) writeini C:\lock.ini main pass $md5($md5($did(mirclock,5)))
  if ( $did(mirclock,6) isnum ) writeini C:\lock.ini main locktime $did(mirclock,6)
  else noop $input(Dude! the time in which the lock is activated must be only in NUMBERS!,o,ERROR,ERROR,ERROR)
  writeini C:\lock.ini main lock $did(mirclock,7).state
  writeini C:\lock.ini main lockstart $did(mirclock,11).state
  dialog -x mirclock mirclock
  mirclock
}

;;; Resetme Alias
;;; - Added to reset to the default '1234' password
;;; if the original ini file is tampered with
alias resetme { writeini C:\lock.ini main pass $md5($md5(1234)) | writeini C:\lock.ini main lock 0 | writeini C:\lock.ini main lockstart 1 | .timerinput $+ $ctime 1 1 return $input(mIRC's lock has been tampered with. The default lock has been re-issued.,wo,Lock Tampered!) }
;;;

alias mirclock {
  goto start
  :start
  ; Next line checks to make sure the lock file hasn't been deleted.
  if (!$isfile(C:\lock.ini)) { resetme | goto start }
  if ($md5($md5($input(mIRC has been locked. Insert your password to unlock it.,wp,mIRC Lock))) != $readini(C:\lock.ini,main,pass)) goto start
  else halt
  :error
  goto start
}
on *:START: {
  ; Next line checks to make sure the lock file has not been deleted.
  if (!$isfile(C:\lock.ini)) { resetme | mirclock }
  if ( $readini(C:\lock.ini,main,lockstart) == 1 ) mirclock
  elseif ( $readini(C:\lock.ini,main,lock) == 1 ) .timerlock -o 1 $readini(C:\lock.ini,main,locktime) mirclock
}
menu channel,status {
  lock mIRC: mirclock
  lock settings: locksettings
}