Hi, I am a beginner of scripting. And I currently encounter some scripting problems: 
1. I don't understand the term "flag" in the tutorials. I mean, what will it do?
2. What does the "x" means in the command flag(x,on)?
3. Can I "see" a flag?
4. Can I make a specific crew member to talk if there is more than one crew member in a room?
I hope my questions will not be too difficult to answer. 
(Sorry for the bad English, if there is any) 
1: Flags is essential to any game/level with some kind of progressing in terms of script - you can use them to make a script only run once, make so a certain flag must be on to do something, and so on.
For example, you can make 2 (or rather 3) scripts like this:
script1
flag(1,on)
say(1)
You've executed this script! Now, you'll have access to script 2 properly!
script2
ifflag(1,script3)
say(2)
Access denied.
You have to execute script1 for this to work!
script3
say(1)
Access granted!
I'm bad at describing things, tell me if you didn't understand!
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2: x means anything. In this case, a number. x is to mark that you can type whatever you want in here.
For example: "say(x)" - you type in whatever you want instead of x (in this case a number between 1 and 5, (and in the 2.1 beta, 1 and 11).
3: You can check if a flag is on by ifflag(x,runscript) (runscript is another script, x is the flag number), if this was what you meant?
4: In the 2.1 beta (you can find this in the VVVVVV Technical Discussion forum), you can use say(x,
crewmate name). This will make the text appear in the color equal to
crewmate name. For example:
say(1,vitellary)
Hi, Vitellary here.