The problem with the value mapping is the loop, so each field element is processed separately as you surmised in your other post.
The simplest answer using functoids is to use a scripting functoid with Inline XSLT. There is no input parameter, but the output is connected to the <name> element in the destination schema.
Here is an example of what the code will look like, however the <name> element and select xpath strings will be different depending on your input and output schemas.
[code:1:f57078d006]<name>
<xsl:value-of select=\"/Root/field[@name =’name’] \"/>, <xsl:value-of select=\"/Root/field[@name = ‘firstName’]\"/>
</name>[/code:1:f57078d006]