posde, as it is a little confusing, and I don't think I fully understand, could you (or someone else) provide a brief description of how an 'EA' (Entertainment Area) and a 'Room' are similar/different. I've always thought I could create more than one EA for a Room (say MD and standalone squeezebox). But to have proper integration I've always had to create a new 'Room' for each media player (MD, squeezebox, etc.). I don't want to hi-jack the thread (happy if this has to go to a new one) but I've wondered.
As posde already stated EA's are intended to be used to create sub-zones in a room and they have to be manually created currently. There does appear to be some pretty arcane bugs in our current support for EA's and it easy to create a 'damaged' EA. It would be good if someone took on the task of debugging this and mapping out where the bugs are. Then one of the devs can pickup this info and work on a fix.
All the best