All the firmware i have flashed have some android apps included, you could just un-install the xbmc you have on and put frodo 12.3 on
now you can backup your xbmc addons, data, etc first if you want to, but that will put all the add-ons back on including ones you might not want
I did a fresh install and put the addons i wanted on so only had what i wanted then backed that up for any other box i bought
let me know if you want to back up and i will explain how to do it
To uninstall xbmc exit out of xbmc then in your apps screen go into settings,apps hi-lite xbmc and press ok
clear cache,clear data then uninstall it (you could also uninstall any other app you don't want in there to)
download xbmc for android here
put it on a sd card/usb stick or external hard drive and put it in the box
in your app screen go to app installer choose you attached drive and install xbmc
once installed you will have to install any add-on you want which you can get from
or
if you need istream or any other addon just let me know
you can set the box to get addons online if you want to do that just let us know