The download worked correctly here, with the 4.51MB AWCSetup.exe file executing properly upon a successful download. The EFW extension is actually characteristic of Computer Associates antivirus, which is integrated into other commercial security suites. It will rename .ZIP and .EXE files as a protective measure under certain circumstances, although exactly what triggers that security feature is uncertain. What I can tell you is that the download is indeed safe, and you should be able to launch the installer by renaming the extension from .EFW to .EXE as it was intended.
Hope this helps,
When I downloaded the latest version it came as an EFW file rather than an exe file. I have no way of accessing this file to upgrade the program. What's up with that?