Assessment mode: modifying course or changing membership states result in RS

deleting or changing content / participants of a course configured in an assessment mode leads to various problems or weird behaviour:

• delete learning area: RS (https://support.frentix.com/otrs/index.pl?Action=AgentZoom&TicketID=3524)
• remove group from course: assessment mode still has removed group configured, student still gets the notification, but can't take the test. see screenshot "removeGroup"
• delete course element: student gets notification of assessment, but can't take the test. see screenshot "removeGroup"
• delete assessment mode: working assessment mode during assessment: warning. delete Assessment mode with corrupt content due to previous fiddling with stuff: Redscreen (https://support.frentix.com/otrs/index.pl?Action=AgentTicketZoom&TicketID=3525#17461)
• delete course: during active assessment mode: redscreen (https://support.frentix.com/otrs/index.pl?Action=AgentTicketZoom&TicketID=3528)