[CONNECT C++] Reading ElementTemplate Components

There are a lot of ElementTemplateParamsHelper::GetXXX methods you can call. Does it your desired ?

Don't see anything that handles ItemTypes in those methods.

You won't find anything. As previously mentioned, none of this stuff is in the published API yet.

If you want an extremely hacky workaround using currently-available APIs, do this:
for each ECInstance on the template:
dynamic_cast it to a DgnElementECInstance
If that succeeds, use GetLocalId() to obtain its xattribute ID, and GetElementRef() to get the element to which it's attached.
If the element is non-null, look up the XAttribute by its ID.
If the XAttribute is found, compare its handler's major version to 22271 and minor version to 2.
That indicates a hidden ECXAttribute, which you can assume is an Item.

If you have not already, please file an enhancement request for the published API to provide straightforward means of interacting with Items associated with Element Templates.

Regards,
Paul

Also, in case it's not obvious - please do not abuse this to make any changes to the Element Template data.

Also, in case it's not obvious - please do not abuse this to make any changes to the Element Template data.