…don’t mix well. In fact, they don’t mix at all.
I don’t know if it’s a bug in either, or simply a bad interaction between the two, but Snow Leopard screwed up 16:9 menus in Adobe Encore, and there’s no known fix to this except moving to the PC.
Essentially what happens is that when you try to create a 16:9 menu in Encore, the selection layer of menu gets squeezed on top and on bottom. Instead of being 16:9, it looks like 2,35:1, and all the graphics in this layer is messed up, truncated, scaled out of proportion, and even sometimes totally breaks down. You won’t see it in the preview in the program itself. You might see it in the DVD image file (haven’t tried it), but you will definitely see it on your DVD player, and wonder what’s going on. Now you know – somebody screwed up big time.
Again, no known workaround, except for moving the whole project to the PC. Filed bug report on Adobe website, but good luck getting any response from these guys.