This is a very early alpha of Techne 2, there right now, there are lots of bugs, many of them severe.
However, with this preview you are able to get a feeling for what's coming.
IMPORTANT: YOU ARE NOT ABLE TO SAVE YOU MODELS
As a side note, I have written an importer and exporter for the new Minecraft Block model format. Those should be working for the most part.
So that could be one way to get your model out of this editor and back into it. Don't blame me if somethign doesn't work though. This version is not ready for produciton use.