I use InDesign regularly but am not that technical with it yet. I'm having a problem where when I make a vector shape, all other vector objects on the page suddenly appear about 20% darker. It's really strange. The same problem has happened when I try to adjust the opacity of an object. I select the object, and as soon as I set the opacity below 100% everything on the page gets darker.
This problem does not effect photos. The problem does effect objects on different layers. So even if I reduce the opacity of an object on the bottom layer, things on the top layer will darken.
Needless to say this problem is making it pretty much impossible to get anything accomplished. It seems to only be happening with certain documents, as sometimes it doesn't happen at all.