You have a precedence problem with the unlink. Since unlink is a list operator and not a unamed unary operator, the statement

  ( -l && !-e && unlink "$File::Find::name" ||
       croak "Warning: couldn't unlink $File::Find::name:$OS_ERROR\n" 
+) unless $param{test};
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actually binds as

  ( -l && !-e && unlink ("$File::Find::name" ||
       croak "Warning: couldn't unlink $File::Find::name:$OS_ERROR\n")
+ ) unless $param{test};
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which is certainly not as you intended. I suggest you add explicit parentheses to the unlink. You could also change the "||" to "or" but parentheses are always clearer. Like this:

  ( -l && !-e && unlink("$File::Find::name") ||
       croak "Warning: couldn't unlink $File::Find::name:$OS_ERROR\n" 
+) unless $param{test};
[download]