Does anyone know what the "is revealing" checkbox means (I'm seeing it in Delphy's CAS tool but I think it is a universal value)? I'm not sure if this is an alpha channel allowance or actually causes the sim wearing the clothing item to be modest (and change for example).

I don't believe it's actually used to define anything by the game, but maybe it's used for the "Inappropriate" trait? It doesn't matter if it's a full parka or an itty bitty bikini - the game doesn't know how much it covers or not, but by ticking that, you can tell it whether -you- think it's revealing. Maybe it was a feature they were going to use and didn't, or will be used in later EPs.

Huh... might have interesting uses one day then. Thanks for the info!