The short answers to all three of these questions are indeed "yes", as the language used in Plus!'s scripting engine is JScript, a rather flexible and easy to learn language.
quote:
Originally posted by Flippy
1. Can I use basic file I/O, like creating a folder in the Common Application Data directory for example? Can I also create files on the fly without getting security exceptions?
Yes, you can, by creating an ActiveXObject:
JScript code:
var x=new ActiveXObject('Scripting.FileSystemObject');
You will have to look up the functions you want on MSDN, though.
quote:
2. Can I use the command line (cmd.exe) and determine what commands to send? If not, can I execute a batch file?
Again, this can be solved using an ActiveXObject:
JScript code:
var y=new ActiveXObject('WScript.Shell');
y.Run('cmd.exe');
quote:
3. Can I display a PNG image (somewhere on the hard disk), either in the current MSN window (probably not), or in a separate window??
This one is a little harder to do, but thanks to Messenger Plus!, we can make our own windows using the Plus! interface, using XML. If you read the Scripting documentation, it has a small introduction to creating your own windows that can be combined with the extra functions in the scripting engine to create a fully functional interface for your scripts.
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4. If I receive a message with emoticons, does the Message string in the script (in the ReceiveMessage event I guess) display the shortcut of the emoticon, or does it simply skip it? In other words, does the 
emoticon come out as or will it be gone from the string?
The returned message will show the emoticon's shortcut.
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5. Can I turn emoticons off temporarily when the user is typing a message the contains the "$$" string? Otherwise, you may get emoticons in your latex string...
As all emotions will be returned as their shortcuts, including custom emotions, it would be impossible to remove their strings from the message. If you mean preventing the actual emoticons displaying while the LaTeX string is being written, there may be some sort of registry edit, for example, that you can change temporarily, but I don't think its effect would be immediate.
Hope this helped
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