Issues with document('file:xxxx') selection - xslt-1.0

Question

In a previous post I asked how to use 2 or more xlm files as input and I got it to work based on the suggested replies when pulling the files from a localhost share.
However when I replace the localhost on a share on a remote host, the files aren't retrieved although I can access them fine on the remote machine under windows.
This is the code I use that works:
<xsl:apply-templates select="document('file://LocalHost/DialStats/InboundStats.xml')" mode="my-mode">
<!-- pass some parameters -->
</xsl:apply-templates>
When I however change that to this then it suddenly fails:
<xsl:apply-templates select="document('file://REG6699SQL01/DialStats/InboundStats.xml')" mode="my-mode">
<!-- pass some parameters -->
</xsl:apply-templates>
I've also tried to add a drive share to my local machine like this:
net use v: \REG6699SQL01\DialStats /USER:
this results in the processing to stop with an error stating that the network path can't be found?
Then I replaced the code to this:
<xsl:apply-templates select="document('file:///V:/InboundStats.xml')" mode="my-mode">
<!-- pass some parameters -->
</xsl:apply-templates>
Which does not cause an error but the result is not as expected, it seems as if the file is blank.
Does any one has ideas as to how this could be resolved or troubleshooted?
Thanks for you time.