You may want to have an exit that you cannot open without a key or other object

1. Go to the exit you want to lock

   

2. Tick the Locked box:

   

3. When you do you need to give a NAME for the “lock”:

   

4. Either write a message or script to explain why:

   

5. Next add in the object to open the door and write a description:

   

6. Click on the Inventory tab and tick the Take box and add a message:

   

7. Click on the Use/Give tab and select Use (on its own):

8. Scroll down the scripts and select Unlock exit:

   

9. Select the name you gave for the unlocking:

   

10. Add in another messages to make it more realistic. I have also added a sound effect:

    

11. Now when you use the Key in the game it will unlock the door:

    

12. Of course the game works much better if you use ONE OBJECT ON ANOTHER OBJECT TO OPEN A DOOR

13. If you do this you need to choose Use this on (another object) to open an exit.

14. Here I have used chewing gum wrapper (OBJECT) on switch box (OBJECT) to unlock lift door (EXIT)