The documentation for XML::Simple says:

The use of this module in new code is discouraged. Other modules are available which provide more straightforward and consistent interfaces. In particular, XML::LibXML is highly recommended.

The major problems with this module are the large number of options and the arbitrary ways in which these options interact - often with unexpected results.

It might as well say:

Abandon all hope, ye who enter here.

If you want stable, reliable XML handling, XML::Simple is really not your friend.

Once the formatting of your question is fixed so I can actually see your XML, I may be able to offer some more specific advice.

Update: the formatting has been fixed, but there still seems to be errors in the listing for your XML. For example, the following is not a valid XML entity reference:

"\&envPageConfig";
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And you show two contradictory listings for the file called envPageConfig.xml.

Try this:

use strict;
use warnings;
use XML::LibXML;


my $file = qq(appsimage_EBSB4.xml);

open my $fh, '<', $file;

binmode $fh;

my $doc = XML::LibXML->load_xml(IO => $fh);

close $fh;

print $doc->toString();

__END__

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE clone [
<!ENTITY envPageConfig SYSTEM "./envPageConfig.xml">
]>
<clone-config>

    <comt4>
        <bolinfpwd>welcome</bolinfpwd>
    </comt4>

</clone-config>
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Edit: forgot my $doc :-(

Please note: your entity should be written as &envPageConfig;, not "&envPageConfig";.

Update:

This might be helpful too:

use strict;
use warnings;
use XML::Twig;
use Data::Dumper;
 
my $file = qq(appsimage_EBSB4.xml);

my $hash_ref = XML::Twig->new()->parsefile( $file )->simplify();

print Dumper($hash_ref);

print $hash_ref->{comt4}->{bolinfpwd};
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Regards, Karl

This part:

my $file = qq(appsimage_EBSB4.xml);
open my $fh, '<', $file;
binmode $fh;
my $doc = XML::LibXML->load_xml(IO => $fh);
close $fh;
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Could be written more succinctly as:

my $doc  = XML::LibXML->load_xml( location => qq(appsimage_EBSB4.xml) 
+);
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toby döt ink

"...written more succinctly..."

Sure tobyink, nothing but the truth. I didn't know this.

To be honest: I'm still using XML::Simple :-[ because i got a lot of config stuff written with it and cheated my example from the docs of XML::LibXML.

N.B.: I also tried XML::LibXML::Simple with the stuff the OP provided, but it failed with the entity...

Best regards, Karl

«The Crux of the Biscuit is the Apostrophe»