I don't think you use wadupdater, but wad inserter.
When you use wad inserter, you need to select the path!
So if you want to ad a car or helmet just type: cars in the path field. when you want to add a steering wheel or a cockpit shape, you need to type: cars\cockpits.
selecht in which directory the file(s) need to be in the wad file.
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