No, AutoIT isn't a plugin. It is a scripting environment to create very easy a mini .net tool to automate administrative work. But wroot answered it correctly. With no scripting experience it is a little bit tricky with autoit.
I can build you a script in a exe-file that is only grab the Windows uername and fill it in the spark property file. Do you need only that kind of dynamic in your property file? All the other parameters are static, like the chat server host and so on, isn't it?
Best,
Benni
