Can't reassign a track to an Environment object in Logic X?

I used to assign a track to an environment object in previous versions, but in Logic X/Yosemite this capacity seems to be missing - meaning I'm totally cut off from using the Environment. In fact, ctrl/click on the track does not even offer the option of reassignment to anything at all. The manual says it can be done?! If this is the case, X is completely useless to me... can anyone verify else correct me please?