Why I am having so many problems ...

Hi, sorry to say the answer to that question is almost certainly "because you made some mistake(s)".

You are quite right that you should not have to, and should not, force installation of a Perl version under perlbrew.

It's really impossible to say from here what the issue is -- only that perlbrew problems always come down to paths, permissions, or both.

I can say that if you follow the documentation exactly it will indeed just work. You may have run something as root when not required, or vice-versa, or may have tried to manually do something ("upgrading patch perl has already been performed" ... should not be needed), or something else.

What I do with OS X is to remove my perls and my development one step further away from the system installation, by using a Linux virtual machine. See VirtualBox and Vagrant. It's very easy and quick. You can get prebuilt images for any flavour you like. If you use Vagrant you can share a directory between the host OS X system and your VMs so you can read/write to docs in both sessions simultaneously.

One of the main advantages to this approach is that if you screw up your system badly when getting it set up, you can just destroy it and start again. And then, once you have a base machine set up as you like it (including perlbrew and a perl or more, all your apps and resources, etc., you can save a copy and clone from it when building new VMs.

A final advantage, depending on how messed up is the system perlbrew installation, is that you could abandon it as is: the system still has the system perl, and in your VMs you are building from scratch. So that would at least get you going sooner, perhaps.

Hope this helps!