Try looking at the module's source code. I quickly found _link_from_token, which contains this:

    if ( $tag eq 'meta' ) {
        my $equiv = $attrs->{'http-equiv'};
        my $content = $attrs->{'content'};
        return unless $equiv && (lc $equiv eq 'refresh') && defined $c
+ontent;

        if ( $content =~ /^\d+\s*;\s*url\s*=\s*(\S+)/i ) {
            $url = $1;
            $url =~ s/^"(.+)"$/$1/ or $url =~ s/^'(.+)'$/$1/;
        }
        else {
            undef $url;
        }
    } # meta
[download]

Does your URL match that regex? Maybe there is a bug.