After updating from MDriven version 7.0.0.14948 to 7.0.0.15936. We have run into a Design Time issue. In the PersistenceMapperProvider file, the PersistenceMapperSQLServer does not work. As soon as you drop PersistenceMapperSQLServer on the PMP file, close it, and reopen there is a Design Time error. Also, we cannot assign DefaultORMappingProvider to PersistenceMapperSQLServer as it is looking for IORMappingProvider, which is unavailable on tools. Please see the attached image for Design Time Errors.
This might be related to problems with different version of DLLs in designer and the GAC. Please have a look at this article in the MDriven wiki https://wiki.mdriven.net/Documentation:Before_going_nuts_about_this_issue