No. Althought I don't have experience in this field, I believe the system offers filesystem change notification, ie. it is the system that detects any change on the disk (and in cache?) and notify the requester: no scan of disk.
I'm curious about how quickly a script with file change notification could react. The file change script would have to be scanning all the folders in every disk, because you could have a script randomly place the plain AutoHotkey script anywhere.
I don't know if that is what shimanov implemented (problem with callback?), but it can be done in another language (at least in C).
I just checked the AU3 link, the sources are indeed quite unreadable, not far of what I suggested, perhaps with additional encryption of strings and numbers, and very long variable names.
The idea of source preprocessor is interesting, I think Laszlo suggested it in days of less advanced syntax (no expressions, etc.): either you write obfuscated code to be more or less decrypted before running, or you write in a slightly different language, more friendly for programmers, to be translated in pure AHK code.