The Revit Clinic has posted a nice little display order workaround for Filled Regions in Title Blocks. I have a feeling that this workaround may also be useful in other situations…
1. Start a new Revit generic annotation family.
2. Cut & paste the filled region[s] into the generic annotation family.
3. Load the generic annotation family into the title block family.
While the display order may appear incorrect in the title block family, it should now appear print in the expected order once loaded back into the project.
Filled Region Blocking your Lines in a Project Title Block? – The Revit Clinic