When running the Introduction to RDT from the Welcome perspective, on step 5, "Switch to Ruby Perspective", I get:
The action could not be run because the class 'org.rubypeople.rdt.internal.cheatsheets.webservice.OpenNewRubyProjectWizardAction' could not be loaded.
This is distro 1.2.2.2, based on Eclipse build id M20070212-1330.