Unfortunately this kind of use-case is not what the Creo View toolkits were built for. They're primarily targeted for embedded Creo View into a different application rather than customizing Creo View itself.
While you could use them to create you're own custom viewer based on Creo View, it would be at the cost of needing to re-implement the majority of the functions simply to prevent printing.
I would recommend taking a look at watermarking either through server based watermarking capabilities (in the Windchill Extensions or Creo View Adapter for PDF) or client based watermarking. This would enable you to make it clear that something is in an unreleased state. Client based watermarking can even have this only appear during printing and not during viewing.
