The easiest way to upgrade the Sales Dashboard project is to use the Upgrade option from the Telerik Data Access menu: screenshot. Another option is to update manually all DataAccess DLLs and the references to them (including the binding redirects in the web.config). The only thing you can do is to replace the old dlls the the new ones and update the OpenAccess references in all projects.
For your convenience I am attaching the updated version of the application, so it is using the latest Open Access version now. I am only removing the Telerik DLLs from the following folders in order to decrease the achieve size, so you will need to add them there on your side:
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