Bug extracting multipart RARs


I found that when extracting a multiple volume RAR which is missing one or more parts somewhere in the middle or at the end, the dialog window freezes and the application starts consuming most of the CPU time. Clicking the dialog window's 'Abort' button doesn't finish the process and the only way I could terminate it was killing the Directory Opus task via the Windows Task Manager. Is this a bug or is something in the settings I should change?