All Spriter Pro owners have access to the Spriter 2 alpha builds which are now updated on a roughly 2 week schedule. We're really sorry for all the long delays to this point and are developing it as fast as we can while simultaneously making sure we don't rush any aspect of it's data format or code base in a way that would cripple it's development in the future. There should be an update any moment now with information on what's currently being worked on and a new build shortly after that. We're doing our best to provide frequent update builds and progress reports as we work towards getting all the core features fully functionally and tied in with each other and the required UI as soon as we can.
We have big plans for features and expansions well beyond the release of version 1.0, which is a big part of why it took us so long to get to this point (making sure the core code and data format are future-proof and will easily support the more advanced features we plan down the line.)