Hi Guys,
Hate to say it but whatever caused the dll issue to be reported, the problem apparently went away. WHich is wierd because I didnt in fact do anything to fix it. Suddenly the project just opened without the error. The apparently blocking plugin was the OceanProject, which was working to the extent that I needed previously. I am currently upgrading to Preview 2 - will be interesting to see if I can get the plugin in and working thereafter - anyway thnks for trying to help.