Sub-assembly custom property linked to a distance mate crashes SolidWorks

I was hoping someone could offer some insight.  We have sub-assemblies that have custom properties linked to a distance mate.  If I open the sub-assembly from the top-level assembly and modify the sub-assemblies custom properties it crashes SW. If I close the top-level it works fine. Any ideas what could be causing this.

 

SW 2023 SP 5