While $read will only return one line, you can make it look like multiple lines by using $crlf in the line that is being read.
Note: In order for this to work, you'll have to drop the n switch from the $read
Another option, that I just thought of, is to format your txt file like this
[topic]
line 1
line 2
line 3
.
.
.
Then use /play -ttopic file.txt
See /help /play for more information.
