The way to configure/add grid shift files in CONNECT edition has changed significantly as a result of major CSMAP library changes. Now it is possible to override any datum definition by adding uncommented entries in a user override file.
Provided with MicroStation in the GeoCoordinateData directory you will notice the presence of a file called UserOverrideGeodeticTransformSeed.asc. The beginning comments explain how to create a file that must be named UserOverrideGeodeticTransform.asc to which you must add the required override entry.
The seed file contains commented all entries that currently make use of grid shift files. It is possible to simply copy the current entry to be modified to the new UserOverrideGeodeticTransform.asc file and uncomment then modify the entry.
For illustration purposes the entry below is the definition of the ED50-IGN.ES datum transformation as delivered with MS CONNECT modified to add a new file. If new files must be added simply add a GRID_FILE line pointing to the new file as the NEW_USER_FILE that was added. Any number of files can be added an as usual former entries have precedence over later entries.
See the file UserOverrideGeodeticTransformSeed.asc for additional details.
Adding a new Grid Shift Override file to MicroStation CONNECT