I have rainlendar.dll and all the plugin dll's in a single folder (named according to the dll version) in my modules folder. I have this definition set:

calendarModule "rainlendar-0.22-rc3"


and then the following:

RainlendarPluginsPath "$ModulesDir$$calendarModule$\"

Events work fine for me with that config. I think you need to use the config dialog to enable the plugins once, too (sets the lines in your rainlendar.ini file).