Skip the 8 Hour ending by editing the .save file.
Locate Save File
First you need to find and backup your save file - this should be in the the AppData folder:
You should have a file named:
Copy and past it somewhere safe.
Modify Save File
Now you want to open your .save file in notepad. You may need to associate it with notepad first by right clicking the file, open with> choose another app, find notepad :)
Yes it looks like a load of junk, but i did the trial and error work already :)
CTRL+F and find the following string:
Should look something like this.
Now the part just before this is what you need to edit, as far as i can tell this controls the timer and always starts with ZB.
So the full line may look like:
Now you just need to change the V to a H in the first part: ZBIIIAVLIKO (his will change depending on what time is left, but the V seems a constant in my testing).
So ZBIIIAVLIKO would then become ZBIIIAHLIKO etc.
CTRL+S to save the file, and relaunch the game.
You should now be at 100% and able to continue killing the red guys!