Upgrade from 18.1.7 to 18.2.5 problem

Hi,
I hope you can help. My assumption is that problem I encounter originates in your security module.
Application attached here works fine on 18.1.7 version (and several versions before that) of your (and Devexpress) library. I tried to upgrade it from 18.1.7 to 18.2.5, but then I got "Saving the 'Aristo.Module.Security.Employee' object is prohibited by security rules." . This is not logged into app log file.

and in next run of app

Executing Sql 'insert into "dbo"."SecuritySystemUserUsers_SecuritySystemRoleRoles"("Roles","Users","OID","OptimisticLockField")values(null,null,@p0,@p1) set @r=1' with parameters '{67d01d41-db56-4299-97d8-868a71d0b7fb},{0},{1}' exception 'System.Data.SqlClient.SqlException (0x80131904): Cannot insert duplicate key row in object 'dbo.SecuritySystemUserUsers_SecuritySystemRoleRoles' with unique index 'iRolesUsers_SecuritySystemUserUsers_SecuritySystemRoleRoles'. The duplicate key value is (, ).
The statement has been terminated.

Same happens in test database I got from backup of production db and in completely new empty db.

Please find attached source code of app, screenshot of first error and app log file

thank you for your help

Goran Sabadoš