Hi Robert, sorry but I'm still a little bit confused. I believe you are talking about importing/reverse engineering a database from an SQL script instead of connecting directly to the database?
Currently such option is not available, you indeed need to connect to database and import model from there.
Data Modeler also helps you in keeping two models for two different database servers, you can convert one model to another with one click, you have an option to use custom data type mapping to help you in that task.