Easy: given $x is a list ref (stored as a hash element in the real program), say print join (',',@$x);

re $VERSION, yea, it's a standard. You found the node on it? Short version for those just tuning in: you can specify a required version number when loading a module and it dies if the module found is too old.

re preserving case but sorting case insensitive: look up the Swartzian Transform (spelling something like that).

I'll go over your code again later tonight, perhaps.

Keep it up!

—John