Signed up especially to thank author of this post.
It works with every theme, just too bad the paths to the .dll's are hardcoded.
Im using a custom theme, not Aero, its just that the file you have to modify has to be located in the Aero folder. Im on Windows 7 Ultimate x64.
---Use my solution for other styles than Aero below at own risk.---
1. If you want this on another theme than Aero make sure the theme you want is NOT selected, also Aero may NOT be select.
2. Backup your shellstyle.dll for your theme you want to mod and for Aero. (Backing up the SysNode64 one and modifying it works exactly as in OP post, so I will not mention it here.)
3. Take ownership of both the one you want to mod and orginal Aero .dll.
4. Delete Aero .dll (orginal, not backup!).
5. Copy the shellstyle.dll you want to modify to the Aero folder.
6. Run authors provided tool, the shellstyle.dll in Aero should now be modified.
7. Copy shellstyle.dll back to the theme you want to mod.
8. Restore original Aero .dll.
9. Select your Theme. This one should be modded and Aero should not be changed.
@Aquifel, maybe this helps you as well.