I wrote a quick and dirty 'mapper' that uses the 1.3 JAR. It reads off the emulator devices, and enumerated ISY programs, scenes and nodes. You double click an item to add/remove it. Seems to work pretty well. Alexa is doing great work with the light management now. The issue I ran into with 'not responding' was for an outletlinc. I couldn't get the REST API to work for either a node, or scene end point. I created a program with a simple then and else clause that changes the state and now Alexa controls that too. I haven't hit the 28 node limit, but with my mapper could test the Echo limits by adding the same device a bunch of times with different names. I ran into a similar problem controlling z-wave door lock state, but wrapped that in a program and voila, Alexa is locking the front door!
I have some polish to put on the mapper (it has very little error handling and some proto-UI stuff) but would be willing to share. I am thinking about adding an automatic update to the Echo as well (forget ++ rediscover) but haven't decided yet if worth the effort...
C.