most likely it is writing with unix rather than dos line endings.
Your processor may have a flag to switch this, or in xslt2 you can add
  
<xsl:output method="text" use-character-maps="eol"/>

  <xsl:character-map name="eol">
    <xsl:output-character character="&#10;" string="&#13;&#10;"/>
  </xsl:character-map>

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