I honestly do not think we're talking to Yosemite surely alter part of the system that are not in Maverick, you can not return to Maverick just down the system and update (which will not be possible that you did not upgrade are different versions, and Yosemite is the most current, that is as if you will install Windows 8 and want to return to Windows 7, it is not possible)
There is more that you back up your information, format and install ... luck, as recommendation never use mac OS betas are always given problems, it does not hurt to wait the final version and is free.