When you say stuff, presumably you have backed up any contacts & photos you wouldn't want to lose? Any paid for former Nokia Store apps. would be a problem if deleted. Inception is going a way back and wondered why you never went down aegis install hack route later. Less likely for anything to go wrong on freshly flashed device, but remember would need to install N9Repomirror to get developer mode to install afterwards.

Thought you might like this work-through in English and attached video:https://techcure.wordpress.com/tag/nokia-n9-ics/

Remember you would need to type in Terminal to remove annoying "Warning you have modified device" screen

I have posted some of terminal output for installing JellyBean upon N9 (too large to include all) as find it much easier to SSH into device and spy/paste to avoid errors: Please note that build.prop & audio_policy.conf have to have .txt removed after download, if using Mac as will be in Plain Text Document format otherwise.


# mkdir /home/nitdroid
~ # tar -xvf /home/user/MyDocs/bootit.tar -C /
./
./opt/
./opt/multiboot/
./opt/multiboot/multiboot-backupmenu.png
./opt/multiboot/multiboot-meego.png
./opt/multiboot/multiboot-android.png
./opt/multiboot/multiboot-sshd.png
./opt/multiboot/multiboot-full.png
./opt/multiboot/root_sshd_config
./opt/backupmenu/
./opt/backupmenu/reboot
./opt/backupmenu/4-Backupmenu-prestart
./opt/backupmenu/files/
./opt/backupmenu/files/usr/
./opt/backupmenu/files/usr/bin/
./opt/backupmenu/files/usr/bin/xzcat
./opt/backupmenu/files/usr/bin/tar
./opt/backupmenu/files/usr/bin/xzfgrep
./opt/backupmenu/files/usr/bin/xzegrep
./opt/backupmenu/files/usr/bin/xzdiff
./opt/backupmenu/files/usr/bin/bunzip2
./opt/backupmenu/files/usr/bin/bzip2recover
./opt/backupmenu/files/usr/bin/bzcat
./opt/backupmenu/files/usr/bin/xz
./opt/backupmenu/files/usr/bin/bzcmp
./opt/backupmenu/files/usr/bin/bzless
./opt/backupmenu/files/usr/bin/xzcmp
./opt/backupmenu/files/usr/bin/bzegrep
./opt/backupmenu/files/usr/bin/bzip2
./opt/backupmenu/files/usr/bin/bzgrep
./opt/backupmenu/files/usr/bin/xzgrep
./opt/backupmenu/files/usr/bin/unxz
./opt/backupmenu/files/usr/bin/lzmainfo
./opt/backupmenu/files/usr/bin/bzmore
./opt/backupmenu/files/usr/bin/xzless
./opt/backupmenu/files/usr/bin/bzdiff
./opt/backupmenu/files/usr/bin/bzfgrep
./opt/backupmenu/files/usr/bin/xzmore
./opt/backupmenu/files/usr/lib/
./opt/backupmenu/files/usr/lib/sftp-server
./opt/backupmenu/files/usr/lib/libz.so.1
./opt/backupmenu/files/usr/lib/libbz2.so.1.0.5
./opt/backupmenu/files/usr/lib/libzip.so.2.1.0
./opt/backupmenu/files/usr/lib/openssh/
./opt/backupmenu/files/usr/lib/openssh/sftp-server
./opt/backupmenu/files/usr/lib/liblzo2.so.2
./opt/backupmenu/files/usr/lib/libzip.so.2
./opt/backupmenu/files/usr/lib/libbz2.so.1.0
./opt/backupmenu/files/usr/sbin/
./opt/backupmenu/files/usr/sbin/sshd
./opt/backupmenu/files/usr/share/
./opt/backupmenu/files/usr/share/doc/
./opt/backupmenu/files/usr/share/man/
./opt/backupmenu/files/usr/share/lintian/
./opt/backupmenu/files/usr/share/lintian/overrides/
./opt/backupmenu/files/usr/share/lintian/overrides/openssh-server
./opt/backupmenu/files/etc/
./opt/backupmenu/files/etc/network/
./opt/backupmenu/files/etc/network/if-up.d/
./opt/backupmenu/files/etc/network/if-up.d/openssh-server
./opt/backupmenu/files/etc/network/if-up.d/drop_gprs_to_sshd
./opt/backupmenu/files/etc/pam.d/
./opt/backupmenu/files/etc/pam.d/sshd
./opt/backupmenu/files/etc/init.d/
./opt/backupmenu/files/etc/default/
./opt/backupmenu/files/etc/default/ssh
./opt/backupmenu/files/var/
./opt/backupmenu/files/var/run/
./opt/backupmenu/files/var/run/sshd/
./opt/backupmenu/4-Backupmenu-start
./opt/backupmenu/3-Backupmenu-preparing
./opt/backupmenu/files.tar
./opt/backupmenu/listbackup.txt
./opt/backupmenu/3-Backupmenu-preparing-files
./opt/backupmenu/map/
./opt/backupmenu/map/6button.map
./opt/backupmenu/backdeb-user.sh
./opt/backupmenu/2-Prestart-Preparing
./opt/backupmenu/datef
./opt/backupmenu/menu/
./opt/backupmenu/menu/m-e-c
./opt/backupmenu/menu/m-b-a
./opt/backupmenu/menu/m-r-r
./opt/backupmenu/menu/m-sshd
./opt/backupmenu/menu/m-e-u
./opt/backupmenu/menu/m-ms
./opt/backupmenu/menu/m-b
./opt/backupmenu/menu/m-r
./opt/backupmenu/menu/m-b-n
./opt/backupmenu/menu/m-r-h
./opt/backupmenu/menu/m-b-r
./opt/backupmenu/menu/m-b-h
./opt/backupmenu/menu/m-e-s-f
./opt/backupmenu/menu/m-r-n
./opt/backupmenu/menu/m-e-s
./opt/backupmenu/menu/m-r-a
./opt/backupmenu/menu/m-e
./opt/backupmenu/1-Welcome
./opt/backupmenu/pass
./sbin/
./sbin/preinit
./sbin/evtap
~ # tar xjvf /home/user/MyDocs/nitdroid_n9_jellybean_alpha5.tar.bz2 -C /home/nit
droid/

default.prop
init
inhome/user/MyDocs/build.prop /home/nitdroid/system/
cp: can't stat '/home/user/MyDocs/build.prop': No such file or directory
~ # cp /home/user/MyDocs/build.prop /home/nitdroid/system/
cp: can't stat '/home/user/MyDocs/build.prop': No such file or directory
~ # cp /home/user/MyDocs/build.prop /home/nitdroid/system/
~ # mv /home/user/MyDocs/power.omap3.so /home/nitdroid/system/lib/hw/power.omap3
.so
~ # cd /home/nitdroid/system/lib/hw/
/home/nitdroid/system/lib/hw # chmod 644 power.omap3.so
/home/nitdroid/system/lib/hw # mv /home/user/MyDocs/audio_policy.conf /home/nitd
roid/system/etc/audio_policy.conf
mv: can't rename '/home/user/MyDocs/audio_policy.conf': No such file or directory
/home/nitdroid/system/lib/hw # mv /home/user/MyDocs/audio_policy.conf /home/nitd
roid/system/etc/audio_policy.conf
/home/nitdroid/system/lib/hw # cd /home/nitdroid/system/etc/
/home/nitdroid/system/etc # chmod 644 audio_policy.conf
/home/nitdroid/system/etc #

Remember that you need to hold down "volume down" when powering on to access boot menu