What is the expected output? From your second attempt, I'm guessing you want all the nodes whose id attribute start with "id".

The following would be what you want, but XML::XSLT doesn't recognize it:

<xsl:if test="/PLMXML/Form[starts-with(@id, 'id')]">
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XML::XSLT doesn't recognize the following either:

<xsl:if test="/PLMXML/Form[substr(@id, 1, 2)='id']">
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XML::XSLT uses its own bad XPath engine instead of a complete, tried and true engine. You should be looking for alternatives.

Update: The above work if you remove the spaces.

<xsl:if test="/PLMXML/Form[starts-with(@id,'id')]">
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