Using Velocity Template Language or SAS code in commom task model of SAS Studio

Question

I trying to create custom task in SAS Studio. I faced with problem, that i can't use variables of <DataSource> or <Option> in XML attributes or in tagged texts.

I need to programm task, that creates a new dataset in predefined library. Name of the dataset may be the same or custom. Here is an example of code:

<?xml version="1.0" encoding="utf-8"?>
<Task schemaVersion="5.0" runNLS="never">
    <Registration>
        <Name>Sample Task</Name>
        <Description>Demonstrates the Common Task Model functionality.</Description>
        <GUID>C6AC34BD-D14A-4CF5-BF2F-A110711BF819</GUID>
        <Procedures>PRINT</Procedures>
        <Version>3.5</Version>
        <Links>
            <Link href="http://www.sas.com">SAS Home page</Link>
        </Links>
    </Registration>
    <Metadata>
        <DataSources>
            <DataSource name="DATASOURCE">
        </DataSource>
        </DataSources>
        <Options>
            <Option name="DATATAB" inputType="string">DATA</Option>
            <Option name="DATAGROUP" inputType="string">DATA</Option>
            <Option name="ROLESGROUP" inputType="string">ROLES</Option>
            <Option name="OPTIONSTAB" inputType="string">OPTIONS</Option>
            <Option name="GROUP" inputType="string">GROUPS</Option>
            <Option name="labelRADIO" inputType="string">Choose name</Option>
            <Option name="nameRadioDefault" variable="radioNameChoice" defaultValue="1" 
                    inputType="radio">$DATASOURCE.getTable()</Option>
            <Option name="nameRadioAlter" variable="radioNameChoice" 
                    inputType="radio">Enter alter name:</Option>
            <Option name="textTableName" defaultValue="" inputType="inputtext" 
                    required="true"
                    indent="1"
                    promptMessage="Enter new table name"
                    missingMessage="Missing text."></Option>
        </Options>
    </Metadata>
    <UI>
        <Container option="DATATAB">
                <DataItem data="DATASOURCE"/>
                <OptionItem option="labelRADIO"/>
                <OptionItem option="nameRadioDefault"/>
                <OptionItem option="nameRadioAlter"/>
                <OptionItem option="textTableName"/>
        </Container>
    </UI>
    <Dependencies>
        <Dependency condition="$radioNameChoice == 'nameRadioDefault'">
            <Target action="disable" conditionResult="true" option="textTableName"/>
        </Dependency>
        <Dependency condition="$radioNameChoice == 'nameRadioAlter'">
            <Target action="enable" conditionResult="true" option="textTableName"/>
        </Dependency>
    </Dependencies>
    <CodeTemplate>
        <![CDATA[
%put DATASET=$DATASOURCE;
%put SASLIBRARY=$DATASOURCE.getLibrary();
%put SASTABLE=$DATASOURCE.getTable(); 
        ]]>
    </CodeTemplate>
</Task>

As result, I have this simple custom task:

In code area, I see reaction by changing options:

Choose another:

But unfortunately, name of radiobutton don't changing. I tried to wrap VTL variable $DATASOURCE.getTable() by <![CDATA[...]]> , but it's not working.

In SAS Studio 3.5: Developer's Guide to Writing Custom Tasks

So my question is it possible to use VTL variables in that way? And if possible, how to realize it?

In SAS Studio 3.5: Developer's Guide to Writing Custom Tasks I can't find answer, but SAS Studio has a complex task as "Join", that has graphical Data Source. And it's not described in Guide. This led to the idea - not all capabilities describe in Guide. If I wrong, please correct Me. Thanks.

Thanks.