I can bring back Core (the old Blue layout) as an unsupported layout. It will not integrate many of the upgrades and will not be upgraded going forward - things like the site rules & staff list will be missing, but if you really want it back I can make it an option.
Bear in mind that the current bulletin board code is not written by me - it is only implemented by me. This means that I am at the mercy of what the actual developers choose to do. They have replaced the old blue layout with the new blue layout (Curve). At the current time, Core is not too far behind in terms of security, but if it gets to the point where it is an exploitable vulnerability I will need to remove it, and will not have much chance to notify you guys beforehand.