Do note the use of chomp. It's much better than those regexps of yours.

Well, no. The OP did mention that the input data comes from a variety of OS's (though he didn't say which OS(s) his script is supposed to run on). Chomp will remove anything at the end of a record that matches "$/", whose default value is OS-dependent, which means that a when a script runs on any sort of unix, chomp will leave a "\r" untouched when the input happens to come directly from a CRLF source.

I would just recommend simplifying the OP's regex:

   s/[\r\n]*$//;
[download]

Also, I'd recommend a while loop instead of  foreach my $line ( <DATA> ), because the for loop causes the entire file to be slurped into a list before the first iteration begins. For small files, that's not a problem, but why invite this sort of trouble if the files happen to get really big?