Ok here's a thought. If the file was signed by HTC, and I hexedited the file, the signing would not be correct anymore. So I've signed the file with a new certificate that I just created. Can anyone test if this does work?
Here's the exe:
HTCFlashlight-nodemo-signed.exe
Here's the cab with my certificate (try without installing this first):
netripper_cert.cab
Just copy the .exe in the same directory as the existing HTCFlashlight.exe and try to run it (make sure you shut down the original app via some task manager first!).
Please let me know if this fixes the problem.