Right, the slow motion issue seems to be related to the PW's campaign generator.
Tested non-generated missions and all work just fine.
Got 7 Co-op missions for tonight, they are made for earlier version of the game,
but I tested 3 of them and saw no issues.
Plane set seems to be:
4 x Nieuport 28.C1
4 x SPAD 13.C1
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4 x Albatros D.Va
4 x Fokker D.VII
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As for the custom skins, upload them and post the linky here and I'll add it to the first post.
Downloading the skins is of course optional.
That is all.
EDIT: First post updated