The dayhack.zip file you have requested: Tools and Utilities / Hacks / Change to Day/Night (DEMO Version) - 0.71kb is not available. Perhaps try browsing all files for the game Need for Speed High Stakes and upload any files you want to share or are missing. This is the only information we could locate:
Need for Speed:High Stakes day/night changer
To use: just run night.reg if you want to race at night, or day.reg if you want to race durring the day.
Troubleshooting: umm...it was probably your fault, but e-mail me anyway.
visit This hack allows you to choose day or night in the Demo version of NFS: High Stakes.