Sorry about the late response. Your previous reply must have gotten lost during my brief vacation.
Currently we mainly recommend making a back-up file with the simple image burner premium plugin for Max2Play. We originally built it to quickly burn new SD cards with fresh images, but we also included a button to save your current install of Max2Play as an .img. This way, you can either save it to a USB storage, a SambaShare, your existing SD or just burn a fresh one with a back-up.
There are also a few buttons to save or restore settings for things like the Squeezebox Server, but backing up is your safest bet for now 😉