Here's a tutorial on how to Hex Edit a hack to make it undetected.
Part 1: Requirements
1.) HxD (Click to Download)
2.) An Injector (PerX, Baldrogs Injector)
3.) Common Sense
Part 2: Editing
1. Open HxD
2. Browse for the dll you're editing.
3. Change "This program must be run under Win32" to anything you want, maintaining the same number of letters (ie. "aaaa aaaaaaa aaaa aa aaa aaaaa aaaaa")
4. Save the file and close HxD
Part 3: Injection
1. Open your injector (On Windows Vista or Windows 7, make sure to run it as Administrator)
2. Enter the process "PBlackout.exe" (Without the " "). If that doesn't work, just type "PBlackout" (Without the " ").
3. Click on Browse, then choose the hack file.
4. Launch Project Blackout.
Credits:
@killbyme - Idea for this tutorial.
@Sketchy - Proof Reading/Editing.