No, you can't just copy it because it contains other values as far as I remember. So it wouldn't work.
But anyway, you don't want to copy it to that locaiton anyway. It's empty because the mod doesn't load anything from there. Don't open CSM. Go to your GP4 directory through Windows Explorer, and then find the 2006/7 mod in the GPSaves>Carsets folder. Then go through the folders until you find a file called slipstream.ini. It may be in a '2006' folder, but that doesn't matter. That's the file that is used. Then just open that manually and change the values in it.
However, having said that, if you really are running it the way you say, then the file in the main directory may work. Because you're basically using CSM to install the mod, and then changing the .exe. But I don't know for certain. So bascially, change the file in the main directory AND change the slipstream.ini in the mod file, and you'll be OK either way
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