I'm sorry if my explanation is kinda vague, but here we go
However, I'm having difficulties in getting the input from the popup window (the true/false result). I've tried using variables and used GetInput function but it failed.
I think there is a similar post to this, but I find out that it uses an ask function if I'm not mistaken. But I feel like the code itself is going to be a tough one to type, and I don't really want to use much of the space in the Quest game screen itself because I worry that the screen will get pretty overcrowded with words which is kinda annoying.
I'm sorry for being overly persistent
I'd suggest something like:
JS.eval ("ASLEvent(confirm('Would you like to skip the intro?')?'SkipIntro':'ShowIntro')")
This will call a Quest function named 'SkipIntro' or 'ShowIntro' depending on which option is chosen.