Backing up the hdd is really not required, unless you are concerned about losing your save games on E:\
Since the smartxx allows ftp transfers from its OS, you can ftp any files you want onto the hdd.
Typically most bioses look for a file called evoxdash.xbe on the c:\ drive as its first boot dash. So if you want to change the dash, rename the default.xbe of whatever dash you want to use, to be called evoxdash.xbe and place the required files in c:\ root. Simple as that.