The Command & Conquer skins were included in Complete Collection and this has been a long running complaint lol. You can just delete the offending skins from your GameData/Skins folder.
You can delete them and that takes a bit of work, but then the game nags you that it needs to be repaired. It's impossible to know if files need to be repaired or if it's the pulled skins causing the issue. It's non-trivial to maintain the game of file shifting. (I keep two sets of skin files on my desk top).
The complete collection? Oh, that could be. I never had that - just bought all the items as they came out.
