Can you first restart all modules i see some modules need to be started, go to Manage module then restartAll. this will trigger all modules to function well behind the scenes. if otherwise, you can restart the whole instance.
Reference application is the mother and father of openmrs as whole, its where all our ,you inclusive all efforts should reside, so it have very many things to do with it.
What was your intension of installating RA in the first case? You can walk around through different modules and get familiar with their functionalities, you can as well create your own module that works as an extension of the reference application and upload it in RA, so feel free to explore more ++ thanks, we would like to here from you