Christopher,
The recommended process to upgrade is the following:
1. Stop your server and then upgrade files on your system with 2.2.0 release ones.
2. Start your server, go to site wide admin, Install software, Upgrade from local. Choose only core packages:
acs-admin
acs-api-browser
acs-authentication
acs-automated-testing
acs-bootstrap-installer
acs-content-repository
acs-core-docs
acs-kernel
acs-lang
acs-mail
acs-messaging
acs-reference
acs-service-contract
acs-subsite
acs-tcl
acs-templating
ref-timezones
search
3. When your server restart, go to install software from local again and then choose the remaining packages.
Once you upgraded, you can add the Kelp theme from /dotlrn/admin, "Site templates".
I hope that will help.
