DOORS 9.7 to DNG 7.0.2 migration - how to create a DNG artifact type given D9 object attribute

The first thing you want to do is run the Migration Metrics Tool and very carefully examine the results. One of the things that's absolutely crucial for a good migration is to do what the Knowledge Center calls "Harmonising the Type System". 

What this basically means is that you need to REALLY carefully examine the attributes and their types and make sure that attributes with the same name have the exact same data type. This means things like Text vs String need to be tidied up, and enumerations need to be the exact same spelling, values, order and content (no missing values). 

This is by far the most tedious part but, if you do it carefully, will get you a really clean migration. See this section:

https://www.ibm.com/docs/en/engineering-lifecycle-management-suite/doors/9.7.2?topic=next-migration-process-phases

Once this is done, create a new single valued enumerated attribute at both Module and Object level and make it the same across all modules. The enumeration values of this attribute must be the exact artifact names in your DNG project area. Then set the value of this attribute for both the DOORS module(s) you're migrating and every object inside them, choosing the artifact type you want the row to become. Then create and export your migration package.

Finally, during the migration package Import process, the wizard will have a section where you can type the attribute name you used for the artifact types at both Module and Object level.

Do a trial migration in a test project area first and look for renamed Artefacts, Attributes and Data Types - these are the ones that haven't been correctly 'harmonised', so go back to your DOORS project and fix them up