[quote user="dominic SEAH"]Some EC features not (currently) supported by Item Types[/quote]
Item Types are a simplified EC Schema. They are intended to be simple to configure by a MicroStation Administrator or power user. Because they are simplified, Item Types lack some advanced features of EC Schema technology.
[quote user="dominic SEAH"]
Dealing with xxx will require a lot of the missing functionality that you listed.
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The functionality isn't missing from EC Schema technology. It's absent from Item Types but it's there, waiting to be used, by an application that makes full use of EC Schema capabilities. You can look at the schemas: they are part of MicroStation CONNECT. You'll find them in folder
C:\Program Files\Bentley\MicroStation CONNECT Edition\MicroStation\ECSchemas
[quote user="dominic SEAH"]Great to see Bentley providing some tools for the average user to manipulate schemas[/quote]
I don't think EC Schema design is best delegated to the 'average user'. Would your IT department assign relational database design to an 'average user'? That's a task of similar complexity that requires deep application domain understanding combined with the ability to interpret user requirements as formal design goals.