[ORD 2019 R2] Preview DGN's - Are Configuration Variables Available to Point to These?

We use a set of non-standard scales and sheet sizes in our Workspace. During our Workspace Migration, with Chuck Lawson's assistance, we were able to preserve these and make them function in ORD without too much effort. It will be one less thing our users have to unlearn and relearn as we move to ORD. However, after Chuck left, it occured to me that one of our "fixes" that made using the current settings might be a non-starter for our consultants.

We needed to make new Preview DGN's for cross section and profile, at a minimum. But if one of our consultants also need to retain the delivered files for other clients, this creates a problem. Ideally, we should be able to place the preview DGN files in their own folder and use a configuration variable to point to that location, so that multiple client workspaces can easily coexist, So my question is this: Is there one or more configuration variable that can be used to point to an alternate location for these files?

If there is not, I believe there needs to be.