The text you are reading in from the file is just that, text. The variables aren't going to get interpolated unless you either eval them, or substitute the variables yourself.

        $conn->me($conn->{channel},eval $txt_me);
        $conn->privmsg($conn->{channel}, eval $txt_chan);
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This doesn't take into account any of the security issues you need to consider when using eval though.

The other option is to do the substitution of any variables in your data file yourself.

$txt_me =~ s/\$nick/$nick/g;
$txt_chan =~ s/\$nick/$nick/g;
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