at least you can see in the list where the missing ones are, it's easy enough to delete the one you dont have, so you dont get a random. Easy enough to add back later if you can work out which is missing, and then find it.
If its real world, is there a results list you can check to compare? Then you know what to search for.
I couldnt remember off hand if it showed in red the missing one, like a missing track in a custom championship does.
The only other option I can think of is, to open the actual preset and go through the driver names until you come across the one that isnt in your skins folder. Enjoy the haystack, hope you find the needle
in case you dont know where the presets are, in your C:\Users\
insert your username on your pc\AppData\Local\AcTools Content Manager\Presets, right click the preset, open with notepad, you should be able to compare the names in the file to the ones in the list in the preset in CM
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