Hi @DavidHogins , the dll file is not at fault, it’s just how the operating system reports an assertion error in the software.
Given that you are using version 5.1.5, could you try the new beta 5.2-rc1? If by chance the error doesn’t happen there, it will be an easy way to fix it.
If it still happens there, sharing the problematic kra file might be the best way to help the developers debug it.