backpedaling from v6 to v5 (some tips) - a retro-migration

I decided to retro-migrate a v6 site to v5 because I really want to use CiviCRM

So here is how I did it, without losing users, nodes etc.

I installed a default version on localhost of v5.10 with the Backup and Migrate module

I copied the existing v6.4 site to localhost, and also installed Backup and Migrate

I exported the db with Backup and Migrate from the v6 site and imported it into v5

I went into modules and disabled all the contrib modules except for core-optional in the v5 site

I uninstalled all the modules that did not have customized settings

(add a field "description" to the system table, I used text/128 as settings)

Run update.php and cron.php

If you have any more errors about missing fields, add those fields to the appropriate tables.

Enable your modules again. Check permissions.

If you had any customized styles (I always put them at the end of style.css in my theme) copy style.css from the v6 theme to the v5 theme

You might need to go over theme configuration settings, block settings etc.

I was able to retro-migrate my theming, my content posts/nodes, site settings, users, roles etc.