Just as the title says -
I have a character who wants a drink - but you don't know that until you ask him how to get into the door he is guarding.
Once you know he wants a drink, I want AGS to enable a dialog option in a SEPERATE conversation so you can then go to the bar and ask for a drink. Unless you have spoken to the other character and discovered that he needs a drink, I don't want the player to be able to ask for one at the bar.
How would I be able to do this?
Bear in mind I have barely touched the scripting yet - so make sure you explain things carefully ;)
BFAQ:Running regular code inside dialogs (http://americangirlscouts.org/agswiki/index.php/Scripting%2C_Code_%26_Interaction#Running_regular_code_inside_dialog)
You can't directly turn options in other dialogs on or off in a dialog, you need to use run-script and dialog_request to call SetDialogOption(). The above BFAQ entry should explain it - if you need more detail try a forum search for run-script and/or dialog_request.