Only the 4 listed ActiveScript engines are supported, only two of which - JS & VBS - are natively available in Windows, while the other two (Pyton & Perl) must be downloaded and installed separately.
I'm not even sure there are any other languages out there that provide ActiveScript support (ActiveScript being a type of engine that can be instanciated by the Windows Scripting Host, which is what Workflow uses).
So beyond the current engines, yes, adding another one would probably represent a vast amount of work. Especially if it's for AWK... which I had to Google to refresh my memory because it's been a such loooooooong while since I've heard a reference to that language! :P
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Technical Product Manager
I don't want to achieve immortality through my work; I want to achieve immortality through not dying - Woody Allen