What you get are the html utf-8 escapes. See this table

Perhaps you should make a proper heather for the page and indicate the encoding using CGI(::something), like

use CGI;
my $cgi=CGI->new();
print CGI->header( -charset=>'utf-8');
[download]

or something similar. You may also try pass your result text through Encode::Detect::Detector and according to the result convert it to be utf-8 or the encoding you need, and substitute the strings in your html code and binmode-ing out as utf-8.

This encoding story can be very twisted so try to make a strategy for that.