Transformation error: itemType, memberTypes

When I transform xsd to tsd4 using schema editor, errors are shown as below.

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The variety “list” cannot be used in TSD4.
The XSD propertyh “itemType” of the “simpleType” definition cannot be used in TSD4.

The variety “union” cannot be used in TSD4.
The XSD property “memberTypes” of the “simpleType” definition cannot be used in TSD4.

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After deleting itemType and memberTypes, everything is okay.

These types are defined in http://www.w3.org/TR/xmlschema-0/#UnionDt

But tamino does not support them?
Or, is there any solution?

Hi Grayger

unfortunately, there are several features in XML Schema which Tamino does not yet support.
As you did, the Tamino Schema Editor can be used to transform a schema to its closest match
supported by the Tamino Server.

Nevertheless, we are working on a better/full support of XML Schema !

Best regards
Uli