[BM SS4] Delete Associative Region: Previous version XFM Feature

Hello.

I've been trying to delete a polygon that is defined as Associative Region: Previous version XFM Feature. I'm working on Bentley Map SS4 but this polygon was most likely created in Bentley Map SS2. I done the process of  "Save as..." > Convert XFM Instances Mode 08.11.07.xx to 08.11.09.xx but I've still got a number of polygons like this one that won't convert.

Is there a way to delete these kinds of elements from the dgn file?

Regards,

Bjorn Magnus

Stod ehf.