Xstore v16.x: Changing base dtx files

Hello,

We have a client that is interested in expanding the primary key of a base Xstore table. We are able to alter the schema, but Xstore's base data definition of the table's primary key needs to be altered to include the new primary key in the generated Id class. However, we don't appear to have access to base table dtx files.

Is there any way we can alter base dtx files or otherwise alter the generated classes?

Thanks,