workflow export to visual studio disabled
as the Nintex Help says: "For Reusable Workflow Templates, the workflow designer ribbon button Export to VS is enabled, allowing users to export the workflow as a '.wsp' file which can be imported into Microsoft Visual Studio 2012."
So it is only available for reusable workflow templates. You can create these via the site menu (below the possibility to create site workflows). As soon as you have published it once, you can use this functionality to export your workflow to a wsp file which can then be imported into visual studio.
Thanks . I would be interested to know the difference between them from architecture and usability purpose, i try searching the web but could not find much. If any one can point out, it will be nice.
Since Nintex is just creating SharePoint 2010 workflows, you should be able to use this Microsoft article as a knowledge base: Introduction to designing and customizing workflows - SharePoint Designer
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