Hey Fabian,
it is important to consider that you will never add anything to MySQL Administrator (except maybe for new graphs, but that is another matter). MA is a tool to show and let you work with a MySQL server and its objects. That means if you want to see a new schema in MA then you have to add this to your server first (you can use MA for that, but there are many other ways to accomplish this task).
Now when you created a model in MySQL Workbench (WB) you can create a physical instance of it in form of one or more schemata. This is called "forward engineering". This can be done in two ways. Either let WB create an SQL script for your model which you can load into MySQL Query Browser (QB) or use the command line interface (CLI) to do that, and which will then execute this script and create whatever objects are contained in this script.
When you have the standard edition (SE) version of WB then you can do that even more conveniently: simply do the forward engineering to a direct database connection. So it will end up directly in your schema instead of taking the extra step of using a script.
In either case, when you are done you can open MA and you will see the new objects. If you left open MA while you did the forward engineering then you will have to manually refresh the schemata list (see context menu in the list of schemata).
Mike
Mike Lischke, MySQL Developer Tools
Oracle Corporation
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