When I try to use an old installer it now loads a laravel version that requires php >= 5.5. The issue is the whole CLASS:: item that is new in php. But since php 5.4 doesn't have this the install fails. How do I install successfully.

Hi, I believe October does a "continuous rolling build" so all installations use the latest version by default. So, you need to upgrade your PHP version if you want to use October CMS.

(PS: I tried downloading the git repo, rolling back to build 318 - http://octobercms.com/changelog and doing a composer update.. However, I found that something is almost always broken with prior versions. Definitely a no-go in production)

You should update your PHP Version. Thats the fastest and easiest solution;)