I don't think I follow you, but it sounds like you've got 3 layers stacked up on top of each other: background (on the bottom, with a pattern in it), layer1 (next up, with say, another pattern in it) and layer2 (above that, with say, a color), and background is set to normal, layers 1 and 2 are set to overlay?
If that's the case, when you overlay them, they become semi-transparent, and interact with all layers below them. I don't know if you've played with Photoshop at all, but the blend modes in photoshop work almost the same as the blend modes in Flash (with some minor differences).
Do I have that right?
thanks for the response, you are exactly right i did some more investigating and found that it isnt possible... i guess it was wishful thinking that i could the seperate layers to ignore each other and only play off of the background.
Depending on the effect you're trying to get, you should look at the other blend modes, like multiply and screen. I think that of the modes I use in all of CS, muliply, screen and overlay are the 3 that get the most use.
Glad I could help, sorry it didn't work like you wanted.